Can Healthy Eating Help You Lose Weight?

Who Benefits Most From A Healthy Diet?

Author: Dr. Stephen Chaney 

fad dietsFad diets abound. High protein, low carb, low fat, vegan, keto, paleo – the list is endless. They all claim to be backed by scientific studies showing that you lose weight, lower your cholesterol and triglycerides, lower your blood pressure, and smooth out your blood sugar swings.

They all claim to be the best. But any reasonable person knows they can’t all be the best. Someone must be lying.

My take on this is that fad diet proponents are relying on “smoke and mirrors” to make their diet look like the best. I have written about this before, but here is a brief synopsis:

  • They compare their diet with the typical American diet.
    • Anything looks good compared to the typical American diet.
    • Instead, they should be comparing their diet with other weight loss diets. That is the only way we can learn which diet is best.
  • They are all restrictive diets.
    • Any restrictive diet will cause you to eat fewer calories and to lose weight.
    • As little as 5% weight loss results in lower cholesterol & triglycerides, lower blood pressure, and better control of blood sugar levels.

Simply put, any restrictive diet will give you short-term weight loss and improvement in blood parameters linked to heart disease, stroke, and diabetes. But are these diets healthy long term? For some of them, the answer is a clear no. Others are unlikely to be healthy but have not been studied long term. So, we don’t know whether they are healthy or not.

What if you started from the opposite perspective? Instead of asking, “Is a diet that helps you lose weight healthy long term?”, what if you asked, “Can healthy eating help you lose weight?” The study (S Schutte et al, American Journal of Clinical Nutrition, 115: 1-18, 2022) I will review this week asked that question.

More importantly, it was an excellent study. It compared a healthy diet to an unhealthy diet with exactly the same degree of caloric restriction. And it compared both diets to the habitual diet of people in that area. This study was performed in the Netherlands, so both weight loss diets were compared to the habitual Dutch diet.

How Was The Study Done?

clinical studyThis was a randomized controlled trial, the gold standard of clinical studies. The investigators recruited 100 healthy, abdominally obese men and women aged 40-70. At the time of entry into the study none of the participants:

  • Had diabetes.
  • Smoked
  • Had a diagnosed medical condition.
  • Were on a medication that interfered with blood sugar control.
  • Were on a vegetarian diet.

The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

The study lasted 12 weeks. The participants met with a dietitian on a weekly basis. The dietitian gave them the foods for the next week and monitored their adherence to their assigned diet. They were advised not to change their exercise regimen during the study.

At the beginning and end of the study the participants were weighed, and cholesterol, triglycerides, and blood pressure were measured.

Can Healthy Eating Help You Lose Weight?

Vegetarian DietTo put this study into context, these were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants lost significant weight on both calorie-restricted diets compared to the group that continued to eat their habitual diet.
    • That is not surprising. Any diet that successfully restricts calories will result in weight loss.
  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).
  • Participants on the high-nutrient quality diet lost 50% more inches in waist circumference than participants on the low-nutrient-quality diet (1.8 inches compared to 1.2 inches).
    • This is a direct measure of abdominal obesity.

When the investigators measured blood pressure, fasting total cholesterol levels, and triglyceride levels:Heart Healthy Diet

  • These cardiovascular risk factors were significantly improved on both diets.
    • Again, this would be expected. Any diet that causes weight loss results in an improvement in these parameters.
  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

Who Benefits Most From A Healthy Diet?

None of the participants in this study had been diagnosed with diabetes when the study began. However, all of them were middle-aged, overweight, and had abdominal obesity. That means many of them likely had some degree of insulin resistance.

Because of some complex metabolic studies that I did not describe, the investigators suspected that insulin resistance might influence the relative effectiveness of the two energy-restricted diets.

To test this hypothesis, they used an assay called HOMA-IR (homeostatic model assessment of insulin resistance). Simply put, this assay measures how much insulin is required to keep your blood sugar under control.

They used a HOMA-IR score of 2.5 to categorize insulin resistance among the participants.

  • Participants with a HOMA-IR score >2.5 were categorized as insulin-resistant. This was 55% of the participants.
  • Participants with a HOMA-IR score ≤2.5 were categorized as insulin-sensitive. This was 45% of the participants.

When they used this method to categorize participants they found:

  • Insulin-resistant individual lost about the same amount of weight on both diets.
  • Insulin-sensitive individuals lost 66% more weight on the high-nutrient-quality diet than the low-nutrient-quality diet (21.6 pounds compared to 13.0 pounds).

The investigators concluded, “Overweight, insulin-sensitive subjects may benefit more from a high- than a low-nutrient-quality energy-restricted diet with respect to weight loss…”

What Does This Study Mean For You?

Questioning WomanSimply put this study confirms that:

  • Caloric restriction leads to weight loss, and…
  • Weight loss leads to improvement in cardiovascular risk factors like total cholesterol, triglycerides, and blood pressure.
    • This is not new.
    • This is true for any diet that results in caloric restriction.

This study breaks new ground in that a high-nutrient quality diet results in significantly better:

  • Weight loss and…
  • Reduction in cardiovascular risk factors…

…than a low-nutrient quality diet. As I said above, the distinction between a “high-nutrient-quality” diet and a “low-nutrient-quality” diet may not be what you might have expected.

  • Both diets were whole food diets. Neither diet allowed sodas, sweets, and highly processed foods.
  • Both included fruits, vegetables, grains, and lean meats.
  • Both reduced caloric intake by 25%.
    • If you want to get the most out of your weight loss diet, this is a good place to start.

In this study the investigators designed their “high-nutrient-quality” diet so that it contained:

  • More plant protein in the form of soy protein.
    • In this study they did not reduce the amount of animal protein in the “high-nutrient-quality” diet. They simply added soy protein foods to the diet. I would recommend substituting soy protein for some of the animal protein in the diet.
  • More fiber.
    • The additional fiber came from substituting whole grain breads and brown rice for refined grain breads and white rice, adding soy protein foods, and adding an additional serving of fruit.
  • More healthy fats (monounsaturated and omega-3 fats).
    • The additional omega-3s came from adding a fish oil capsule providing 700mg of EPA and DHA.
  • Less simple sugars. While this study focused on fructose, their high-nutrient-quality diet was lower in all simple sugars.

ProfessorAll these changes make great sense if you are trying to lose weight. I would distill them into these 7 recommendations.

  • Follow a whole food diet. Avoid sodas, sweets, and highly processed foods.
  • Include all 5 food groups in your weight loss diet. Fruits, vegetables, whole grains, dairy, and lean proteins all play an important role in your long-term health.
  • Eat a primarily plant-based diet. My recommendation is to substitute plant proteins for at least half of your high-fat animal proteins. And this study reminds us that soy protein foods are a convenient and effective way to achieve this goal.
  • Eat a diet high in natural fibers. Including fruits, vegetables, whole grains, beans, nuts, seeds, and soy foods in your diet is the best way to achieve this goal.
  • Substitute healthy fats (monounsaturated and omega-3 fats) for unhealthy fats (saturated and trans fats) in your diet. And this study reminds us that it is hard to get enough omega-3s in your diet without an omega-3 supplement.
  • Reduce the amount of added sugar, especially fructose, from your diet. That is best achieved by eliminating sodas, sweets, and highly processed foods from the diet. I should add that fructose in fruits and some healthy foods is not a problem. For more information on that topic, I refer you to a previous “Health Tips” article .
  • Finally, I would like to remind you of the obvious. No diet, no matter how healthy, will help you lose weight unless you cut back on calories. Fad diets achieve that by restricting the foods you can eat. In the case of a healthy diet, the best way to do it is to cut back on portion sizes and choose foods with low caloric density.

I should touch briefly on the third major conclusion of this study, namely that the “high-nutrient quality diet” was not more effective than the “low-nutrient-quality” diet for people who were insulin resistant. In one sense, this was not news. Previous studies have suggested that insulin-resistant individuals have more difficulty losing weight. That’s the bad news.

However, there was a silver lining to this finding as well:

  • Only around half of the overweight, abdominally obese adults in this study were highly insulin resistant.
    • That means there is a ~50% chance that you will lose more weight on a healthy diet.
  • Because both diets restricted calories by 25%, insulin-resistant individuals lost weight on both diets.
    • That means you can lose weight on any diet that successfully reduces your caloric intake. That’s the good news.
    • However, my recommendation would still be to choose a high-nutrient quality diet that is designed to reduce caloric intake, because that diet is more likely to be healthy long term.

The Bottom Line 

A recent study asked, “Can healthy eating help you lose weight?” This study was a randomized controlled study, the gold standard of clinical studies. The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

These were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).

When the investigators measured cardiovascular risk factors at the end of 12 weeks:

  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

For more details on this study, what this study means for you, and my 7 recommendations for a healthy weight loss diet, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Do Whole Grains Reduce Inflammation?

Are Low Carb Diets Healthy Long Term?

Author: Dr. Stephen Chaney 

InflammationInflammation is a bit like Dr. Jekyll and Mr. Hyde. Acute inflammation plays a valuable role in our immune response. But chronic inflammation is a scourge. Chronic inflammation:

  • Is a key component of all the “itis” diseases.
  • Can lead to autoimmune diseases.
  • Is thought to play an important role in heart disease.
  • Is associated with many other diseases, such as diabetes, cancer, Alzheimer’s disease, and inflammatory bowel diseases (IBS).

While there are many causes of chronic inflammation, diet plays an important role. In a previous issue of “Health Tips From the Professor” I have described how an anti-inflammatory diet can quell the fires of chronic inflammation.

Fiber from unprocessed plant foods is a key component of an anti-inflammatory diet. But are all plant fibers equally effective at reducing inflammation? Here is what we know:

  • Fiber from whole grains, vegetables, and fruits have different chemical and physical characteristics and support the growth of different species of friendly bacteria in our intestines.
  • Previous studies have shown that higher intakes of dietary fiber are associated with lower risk of heart disease.
    • Studies have suggested that fiber from whole grains may be more effective than fiber from fruits and vegetables at reducing heart disease risk.
  • Chronic inflammation is highly associated with the development of heart disease. This has led to the hypothesis that fiber from whole grains may be more effective than other plant fibers at reducing chronic inflammation.
    • Some studies have supported this hypothesis, but they have all been done with middle-aged participants, not with elderly participants who characteristically have higher levels of inflammation.

The study (R Shivakoti et al, JAMA Network Open, 5(3): e225012, 2022) I will describe today was designed to:

  • Test the hypothesis that whole grain fiber is more effective than vegetable or fruit fiber at reducing inflammation.
  • Determine how important reducing inflammation is at reducing the risk of heart disease.
  • Extending these findings to an older population group.

How Was The Study Done?

Clinical StudyThe data for this study was obtained from the Cardiovascular Health Study (CHS), a study designed to characterize factors influencing cardiovascular health in American adults aged 65 years or older. This study analyzed data from 4,125 participants (40% men, 95% white) who enrolled in the CHS study from 1989 to 1990.

These participants did not have heart disease at the time they were enrolled in the study. They had an average age of 72.6 at the beginning of the study and were followed for an average of 11.9 years. During that time 1,941 (47%) of them developed heart disease.

When the participants were enrolled in the study:

  • A food frequency questionnaire was administered to them by a trained dietitian to assess their long-term usual dietary intake. This information was used to assess:
    • Their total fiber intake and…
    • Their fiber intake from various dietary sources (whole grains, vegetables, and fruits).
  • Fasting blood samples were collected and used to analyze various markers of inflammation.

A follow-up via phone was conducted every 6 months to track an initial diagnosis of cardiovascular disease.

At the end of the study, the investigators analyzed:

  • The effect of total fiber and fiber from different food sources on the risk of developing heart disease.
  • The effect of total fiber and fiber from different food sources on inflammatory markers in the blood.
  • The extent to which decreased inflammation could explain the effect of whole grain fiber on reducing heart disease.

Do Whole Grains Reduce Inflammation?

With respect to inflammation:

  • Increased intake of total fiber was associated with healthier levels of the inflammatory markers CRP, IL-1RA, and sCD163.
    • Increased intake of fiber from whole grains was associated with healthier levels of the inflammatory markers CRP, IL-6, and IL-1RA.
    • Increased intake of vegetable fiber was not significantly associated with healthier levels of any inflammatory marker.
    • Increased intake of fiber from fruits was associated with healthier levels of the inflammatory marker sCD163.

With respect to cardiovascular disease:

  • Every 5g/day increase in total fiber decreased the risk of heart disease by 5%.
    • Every 5g/day increase in fiber from whole grains decreased the risk of heart disease by 14%.
    • Increased intake of fiber from vegetables and fruits did not have a statistically significant effect on the risk of heart disease.

Finally, when the investigators did a statistical analysis to determine to extent to which the effect of whole grain fiber on inflammation, could explain its effect on heart disease, they concluded:

  • The effect of whole grain fiber on inflammation could explain only about 16% of its effect on heart disease.

In the words of the authors, “In this prospective study of older adults, higher intakes of total fiber were associated with lower levels of various inflammatory markers, and this inverse association was primarily due to cereal fiber intake. Vegetable and fruit fiber intakes were not consistently associated with lower levels of inflammatory markers. These results suggest that specifically cereal fibers might be more effective in reducing systemic infection, which will need to be tested in interventional studies of specific populations.

In addition, cereal fiber was associated with a lower risk of CVD, although inflammation mediated less than 20% of the observed inverse association between cereal fiber and CVD. This suggests that the association of cereal fiber is primarily due to factors … other than systemic inflammation.”

Note: This conclusion underplays the role of fruit fiber in reducing inflammation. The statement is correct in saying only whole grain fiber reduces the inflammatory markers CRP, IL-6, and IL-1RA. However, both total fiber and fruit fiber increase the anti-inflammatory marker sCD163. That is why I chose to use the term “healthier levels” rather than lower or higher levels when describing the effects of whole grain and fruit fibers on markers of inflammation.

What Does This Study Mean For You?

confusion#1: The biggest takeaway from this study is that whole grains are good for you.

  • This study shows that whole grain fiber decreases our risk of developing heart disease.
    • This is fully consistent with multiple previous studies showing that whole grains decrease the risk of heart disease.
    • Previous studies have also shown that whole grains reduce the risk of cancer and diabetes.
  • This study also suggests that whole grain fiber reduces chronic inflammation.

There are also some takeaways from this and previous studies that may not be so obvious.

#2: Fiber has many important benefits beyond its effect on inflammation. For example:

  • This study concluded that the reduction in inflammation only explained a small part of the beneficial effect of whole grain fiber on reducing heart disease risk.
  • That is because whole grain fiber also:
    • Feeds friendly bacteria that improve gut function.
    • Provides satiety that can result in reduced fat and calorie intake.
    • Binds cholesterol, which improves blood cholesterol level.
    • Slows the rate at which dietary sugar enters the bloodstream, which improves blood sugar control.

#3: Whole plant foods have many benefits beyond their fiber content.

  • This study concluded that whole grain fiber was more beneficial than fiber from fruits and vegetables at reducing inflammation and reducing the risk of heart disease.
  • Previous studies have also shown that fruit and vegetables significantly decrease the risk of heart disease, stroke, and cancer.
  • That is because whole grains and unprocessed fruits and vegetables:
    • Displace sugar, refined flour, and highly processed foods from the diet.
    • Have a lower caloric density than processed foods, making it easier to achieve a healthy weight.
    • Provide nutrients and phytonutrients not found in processed foods.
    • Support a wide variety of healthy gut bacteria.

Are Low Carb Diets Healthy Long Term?

low carb dietconfusionWhen you consider all the benefits of whole grains, fresh fruits, and vegetables, it brings us to the final take home message.

#4: Despite what Dr. Strangelove has told you, low-carb diets may not be healthy long term.

  • There are no long-term (10 or 20-year) studies of low-carb diets. We simply have no evidence to support the claim that they are healthy long term.
  • Most low-carb diets eliminate or severely limit fruits and whole grains. Considering the many health benefits they provide, it is unlikely that any diet that restricts them is healthy long term.

The Bottom Line 

A recent study looked at the effect of plant fiber on inflammation and on heart disease.

With respect to inflammation the study found:

  • Increased intake of total fiber was associated with healthier levels of the inflammatory markers CRP, IL-1RA, and sCD163.
    • Increased intake of fiber from whole grains was associated with healthier levels of the inflammatory markers CRP, IL-6, and IL-1RA.
    • Increased intake of vegetable fiber was not significantly associated with healthier levels of any inflammatory marker.
    • Increased intake of fiber from fruits was associated with healthier levels of the inflammatory marker sCD163.

With respect to cardiovascular disease:

  • Every 5g/day increase in total fiber decreased the risk of heart disease by 5%.
  • Every 5g/day increase in fiber from whole grains decreased the risk of heart disease by 14%.
    1. The biggest takeaway from this study is that whole grains are good for you.

 Other takeaways from this and previous studies are:

2) Fiber has many important benefits beyond its effect on inflammation.

3) Whole plant foods have many benefits beyond their fiber content.

4) Despite what Dr. Strangelove has told you, low-carb diets may not be healthy long term.

For more details on this study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Can Diet Add Years To Your Life?

Which Foods Have The Biggest Effect On Longevity? 

Author: Dr. Stephen Chaney

Fountain Of YouthEveryone over 50 is searching for the elusive “Fountain Of Youth”.

  • We want to look younger.
  • We want to feel younger.
  • We want the energy we had in our 20s.
  • We want to be rid of the diseases of aging.

The list goes on!

But how do we do that? Pills and potions abound that claim to reverse the aging process. Most just reverse your wallet.

  • Should we train for marathons or bodybuilding contests?
  • Should we meditate or do yoga to relieve stress?
  • Should we get serious about losing weight?
  • Should we get more sleep?
  • Is there some miracle diet that can slow the aging process?

All the above probably slow the aging process, but the evidence is best for the effect of diet on aging. Several recent meta-analyses have looked at the effect of diet on the risk of premature deaths. In this issue of “Health Tips From the Professor” I review a study (LT Fadnes et al, PLoS Medicine, February 8, 2022) that combines the best of these meta-analyses into a single database and provides a provocative insight into the effect of diet on longevity.

How Was This Study Done?

Clinical StudyThis study combined data from recent meta-analyses looking at the impact of various food groups on the risk of premature deaths with the Global Burden of Disease Study which provides population-level estimates of life years lost due to dietary risk factors.

The authors then developed a new algorithm that allowed them to estimate how different diets affect sex- and age-specific life expectancy.

They divided the population into three different diet categories based on their intake of whole grains, vegetables, fruits, nuts, legumes, fish, eggs, dairy, refined grains, red meat, processed meat, white meat, sugar-sweetened beverages, and added plant oils. The diet categories were:

  • Typical Western Diet (TW). This diet was based on average consumption data from the United States and Europe. This was their baseline.
  • Optimal diet (OD). This diet is similar to a vegan or semi-vegetarian diet. However, it was not a purely vegan diet nor a purely semi-vegetarian diet. Instead, it represented the best diet people in this study were consuming.
  • Feasibility diet (FA). This diet recognizes that few people are willing to make the kind of changes required to attain an optimal diet. It is halfway between the Typical Western Diet and the Optimal Diet.

To help you understand these diets based on the foods the study participants were eating, here are the comparisons in terms of daily servings:

Food TW Diet FA Diet OD Diet
Whole grains 1.5 servings 4.3 servings 7 servings
Vegetables 3 servings 4 servings 5 servings
Fruits 2.5 servings 3.75 servings 5 servings
Nuts 0 serving* 0.5 serving* 1 serving*
Legumes 0 serving** 0.5 serving** 1 serving**
Fish 0.25 serving 0.5 serving 1 serving
Eggs 1 egg 0.75 egg 0.5 egg
Dairy 1.5 servings 1.25 servings 1 serving
Refined grains 3 servings 2 servings 1 serving
Red meat 1 serving 0.5 serving 0 serving
Processed meat 2 servings 1 serving 0 serving
White meat 0.75 serving 0.6 serving 0 serving
Sugar-sweetened beverages 17 oz 8.5 oz 0 oz
Added plant oils 2 tsp 2 tsp 2 tsp

*1 serving = 1 handful of nuts

**1 serving = 1 cup of beans, lentils, or peas

Using their algorithm, the authors asked what the effect on longevity would be if people changed from a typical western diet to one of the other diets at age 20, 60, or 80 and maintained the new diet for at least 10 years. The 10-year requirement is based on previous studies showing that it takes around 10 years for dietary changes to affect the major killer diseases like heart disease, cancer, or diabetes.

Finally, the authors improved the accuracy of their estimates of the effect of diet on longevity by taking into account the quality of each study included in their analysis. I will discuss the importance of this below.

Can Diet Add Years To Your Life?

The results were impressive.

The authors estimated that if people in the United States were to change from a typical western diet to an “optimal diet” and maintain it for at least 10 years,

…starting at age 20, men would live 13 years longer and women would live 10.7 years longer.

…starting at age 60, men would live 8.8 years longer and women would live 8 years longer.

…starting at age 80, both men and women would live 3.4 years longer.

But what if you weren’t a vegan purist? What if you only made half the changes you would need to make to optimize your diet? The news was still good.

The authors estimated that people in the United States were to change from a typical western diet to a “feasibility diet” and maintain it for at least 10 years,

…starting at age 20, men would live 7.3 years longer and women would live 6.2 years longer.

…starting at age 60, men would live 4.8 years longer and women would live 4.5 years longer.

…starting at age 80, both men and women would live ~2 years longer.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.”

Which Foods Have The Biggest Effect On Longevity?

The algorithm the authors developed also allowed them to look at which foods have the biggest effect on longevity. The authors estimated when changing from a typical western diet to an optimal diet, the greatest gains in longevity were made by eating:

  • More legumes, whole grains, and nuts, and…
  • Less red and processed meat.

The authors concluded, “An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains [in longevity].”

However, this conclusion needs to be interpreted with caution. We also need to recognize that an “optimal diet” was defined as the best diet people in this study were eating. In addition, the effect of different foods on longevity depends on:

  • The quality of the individual studies with that food, and…
  • The difference in consumption of that food in going from a western diet to an optimal diet.

For example:

  • Legumes, whole grains, nuts, red & processed meat made the list because the quality of data was high and the difference in consumption between the typical western diet and optimal diet was significant.
  • The quality of data for an effect of fruits and vegetables was also high. For example, one major study concluded that consuming 10 servings a day of fruits and vegetables a day reduces premature death by 31% compared to consumption of less than 1 serving a day. However, the difference in consumption of fruits and vegetables between the western and optimal diets in this study was small, so fruits and vegetables didn’t make the list.
  • Eggs and white meat didn’t make the list because the quality of data was low for those foods. Simply put,  that means that there was a large variation in effect of those foods on longevity between studies.
  • Other foods didn’t make the list because the quality of data was only moderate and/or the difference in intake was small.

So, the best way to interpret this these data is:

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve these benefits. In the words of the authors, “Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

What Does This Study Mean For You?

This study is the best of many studies showing the benefit of a more plant-based diet on health and longevity. It particularly encouraging because it shows:

  • You can achieve significant benefit by switching to a more plant-based diet late in life. You get the biggest “bang for your buck” if you switch at age 20. But even making the switch at age 60 or 80 was beneficial.
  • You don’t need to be a “vegan purist”. While the biggest benefits were seen for people who came close to achieving a vegan or semi-vegetarian diet, people who only made half those changes saw significant benefits.

As I said above, this is a very strong study. However, the underlying data come from association studies, which can have confounding variables that influence the results.holistic approach

For example, people who eat more plant-based diets tend to weigh less and exercise more. And both of those variables can influence longevity. Each study attempted to statistically correct for those variables, but they still might have a slight influence on the results.

However, I don’t see that as a problem because, in my view, a holistic approach is always best. As illustrated on the right, we should be seeking a lifestyle that includes a healthy diet, weight control, and exercise.

As for supplementation, both the vegan and semi-vegetarian diets tend to leave out whole food groups. Unless you are married to a dietitian, that means your diet is likely to be missing important nutrients.

The Bottom Line

A recent study asked whether changing from the typical western diet to a healthier, more plant-based diet could influence longevity. The results were very encouraging. The study showed that:

  • Changing to a healthier diet could add up to a decade to your lifespan.
  • The improvement in lifespan was greatest for those whose diets approached a vegan or semi-vegetarian diet, but a significant improvement in lifespan was seen for people who made only half those dietary improvements.
  • The improvement in lifespan was greatest for those who switched to a healthier diet in their 20’s, but significant improvements in lifespan were seen for people who didn’t change their diet until their 60’s or 80’s.

In terms of the foods that have the biggest effect on longevity.

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve those benefits.
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.

An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains. Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”

For more details about this study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Does Olive Oil Help You Live Longer?

Which Fat Is Healthiest?

Author: Dr. Stephen Chaney

If you believe the headlines, olive oil is a superfood. It is often described as the star of the Mediterranean diet. It is referred to as the healthiest of dietary fats. Is this true, or is it hype?

Olive oil’s resume is impressive:

  • It is rich in monounsaturated fatty acids, which…
    • Are less susceptible to oxidation than polyunsaturated oils.
    • Make our arteries more flexible, which lowers blood pressure.
    • Lower LDL-cholesterol levels, which reduces the risk of heart disease.
  • Extra-virgin olive oil contains phytonutrients and tocopherols (various forms of vitamin E), which…
    • Have anti-inflammatory properties.
    • Improve insulin sensitivity and blood sugar control.
  • Olive oil consumption is also associated with healthier gut bacteria, but it is not clear whether this is due to olive oil or to the fact that a Mediterranean diet is also richer in fresh fruits, vegetables, and whole grains.

Several recent studies have shown that olive oil consumption is associated with a lower risk of heart disease. However, these studies were conducted in Mediterranean countries where the average intake of olive oil (3 tablespoons/day) is much greater than in the United States (0.3 tablespoons/day).

The current study (M Guasch-Ferré et al, Journal of the American College of Cardiology, 79: 101-112, 2022) was designed to test whether:

  • The amount of olive oil Americans consume decreases the risk of heart disease.
  • Whether olive oil consumption had benefits beyond a reduction in heart disease risk.

How Was This Study Done? 

Clinical StudyThis study combined data from 60,582 women enrolled in the Nurses’ Health Study and 31,801 men enrolled in the Health Professionals Follow-Up Study). The participants:

  • Were free of heart disease and diabetes at the start of the study.
  • Were 56 at the start of the study with an average BMI of 25.6 (Individuals with BMIs in the 25-30 range are considered overweight, so they were at the lowest end of the overweight range).

The Nurses’ Health Study and Health Professional Follow-Up Study are both association studies, meaning they looked at the association between olive oil consumption and health outcomes. They cannot directly prove cause and effect. However, they are very strong association studies because:

  • Every 2 years, participants filled out a questionnaire that updated information on their body weight, smoking status, physical activity, medications, multivitamin use, and physician-diagnosed diseases.
  • Every 4 years, participants filled out a comprehensive food frequency questionnaire.
  • In other words, this study did not just rely on the participant’s lifestyle, dietary intake, and health at the beginning of the study, as so many association studies do. It tracked how each of these variables changed over time.

The participants were followed for an average of 28 years and their average olive oil intake over those 28 years was correlated with all-cause mortality and mortality due to specific diseases.

  • Deaths were identified from state vital statistics, the National Death index, reports by next of kin, or reports by postal authorities.
  • Causes of death were determined by physician review of medical records, medical reports, autopsy reports, or death certificates.

Does Olive Oil Help You Live Longer?

During the 28 years of this study:

  • Olive oil consumption in the United States increased from an average of ~1/3 teaspoon/day to ~1/3 tablespoon/day.
  • Margarine consumption decreased from 12 g/day to ~4 g/day.
  • The consumption of all other fats and oils remained about the same.

As I mentioned above, olive oil consumption was averaged over the life of the study for each individual. When the investigators compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 35% for the group consuming the most olive oil.

However, the group consuming the most olive oil also was more physically active, had a healthier diet, and consumed more fruits and vegetables than the group who consumed the least olive oil.

  • After correcting for all those factors, mortality from all causes was decreased by 19% for the group consuming the most olive oil.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total…mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.” (I will fill in the blanks in this statement once I have covered other aspects of this study)

The authors also said, “Of note, our study showed that benefits of olive oil can be observed even when consumed in lower amounts than in Mediterranean countries.”

Are There Other Benefits From Olive Oil Consumption?

Mediterranean dietThe study didn’t stop there. The investigators also looked at the effect of olive oil consumption on the major killer diseases in the United States and other developed countries. When they compared the effect of olive oil consumption on cause-specific mortality, they found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.
    • The reduction in neurodegenerative disease was much greater for women (34% decrease) than for men (19% decrease).

With this information I can fill in one of the blanks in the author’s conclusions: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.”

Which Fats Are Healthiest?

Good Fat vs Bad FatThe sample size was large enough and the dietary information complete enough for the investigators to also estimate the effect of substituting olive oil for other dietary fats and oils.

They found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
    • The same beneficial effects of substituting olive oil for other fats were seen for cause-specific mortality (cardiovascular disease, cancer, respiratory disease, and neurodegenerative disease).
    • There was a linear dose-response. This means that substituting twice as much olive oil for other dietary fats doubled the beneficial effects on total and cause-specific mortality.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

Now I can fill in the remaining blanks in the author’s conclusion: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

What Does This Study Mean For Us?

ConfusionAs I said above, this is an association study, and association studies do not prove cause and effect. However:

1) This is a very strong association study because:

    • It is a very large study (92,383 participants).
    • It followed the participants over a long time (28 years).
    • It utilized a very precise dietary analysis.
    • Most importantly, it tracked the participant’s lifestyle, dietary intake, and health at regular intervals throughout the study. Most association studies only measure these variables at the beginning of the study. They have no idea how they change over time.

2) This study is consistent with several previous studies showing that olive oil consumption decreases the risk of dying from heart disease.

3) This study draws on its large population size and precise dietary analysis to strengthen and extend the previous studies. For example:

    • The study showed that increased olive oil consumption also reduced total mortality and mortality due to cancer, respiratory disease, and neurodegenerative disease.
    • The study measured the effect of substituting olive oil for other common dietary fats.
    • The study showed that increased olive oil consumption in the context of the American diet was beneficial.

I should point out that the headlines you have seen about this study may be misleading.

  • While the headlines may have depicted olive oil as a superfood, this study did not find evidence that olive oil was more beneficial than other unsaturated vegetable oils. Again, this is consistent with many previous studies showing that substituting vegetable oils for other dietary fats reduces the risk of multiple diseases.
  • The headlines focused on the benefits of increasing olive oil consumption. However, they neglected the data showing that increasing olive oil (and other vegetable oils) was even more beneficial (35% reduction in total mortality) in the context of a healthy diet – one with increased intake of fruits, vegetables, whole grains, nuts, legumes, and long-chain omega-3s and decreased intake of red & processed meats, sodium, and trans fats.

So, my recommendation is to follow a whole food, primarily plant-based diet and substitute extra-virgin olive oil and cold pressed vegetable oils for some of the animal fats in your diet.

Some vegan enthusiasts recommend a very low-fat whole food plant-based diet. They point to studies showing that such diets can actually reverse atherosclerosis. However:

  • Those studies are very small.
  • The overall diet used in those studies is a very healthy plant-based diet.
  • The studies did not include a control group following the same diet with olive oil or other vegetable oils added to it, so there is no comparison of a healthy vegan diet with and without vegetable oils.

If you have read my book, Slaying the Food Myths, you know that my recommendations encompass a variety of whole food, primarily plant-based diets ranging all the way from very-low fat vegan diets to Mediterranean and DASH diets. Choose the one that best fits your food preferences and the one you will be most able to stick with long term. You will be healthier, and you may live longer.

The Bottom Line

A recent study looked at the effect of olive oil consumption on the risk dying from all causes and from heart disease, cancer, respiratory disease, and neurodegenerative diseases. When the study compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 19% for the group consuming the most olive oil.

They also found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.

They also found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

For more details and a summary of what this study means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Do Whole Grains Keep Diabetes Away?

Are Whole Grains Healthy? 

Author: Dr. Stephen Chaney

deceptionLow carb enthusiasts will tell you that carbohydrates are the villain. They tell you that cutting carbohydrates out of your diet will reduce your risk of obesity, diabetes, heart disease, and cancer.

If they limited their list of villainous foods to highly processed foods with white flour and/or added sugars, many nutrition experts would agree with them. There is widespread agreement in the nutrition community that we eat far too much of these foods.

However, I don’t have to tell you that many low carb diets also eliminate whole grains, fruits, and beans from their diets based solely on the carbohydrate content of these foods. Is this good advice? Is there any data to back up this claim?

The short answer is no. Last week I shared a study showing that fruits reduced your risk of developing type 2 diabetes.

This week I will review a study looking at the effect of whole grain consumption on the risk of developing type 2 diabetes.

How Was This Study Done?

Clinical StudyThis study combined data from women in the Nurses’ Health Study (1984-2014) and the Nurses’ Health Study II (1991-2017), and men in the Health Professionals Follow-Up Study (1986-2016). There were 158,259 women and 36,525 men in these three studies.

None of the participants had type 2 diabetes, cardiovascular disease, or cancer at the time they entered the studies.

At the beginning of each study and every 4 years later the participants were asked to fill out a food frequency questionnaire to collect information about their usual diet over the past year. Validation studies showed that the diets of the participants changed little over the interval of the studies. [Note: This is a strength of these studies. Many clinical studies only collect dietary data at the beginning of the study, so there is no way of knowing whether the participant’s diets changed over time.]

The participants in these studies were followed for an average of 24 years. They were sent follow-up questionnaires every two years to collect information on diseases they had been diagnosed with over the past two years. Participants who reported type 2 diabetes were sent a supplementary questionnaire to confirm the diagnosis.

This study measured the effect of whole grain consumption, and frequently consumed whole grain foods, on the long term (24 year) risk of developing type 2 diabetes.

The data were adjusted for multiple possible confounding variables (other factors that might affect the risk of developing type 2 diabetes) including age, ethnicity, smoking status, alcohol intake, multivitamin use, healthy eating index (a measure of how healthy the overall diet was), caloric intake, obesity, family history of diabetes, and use of oral contraceptives or postmenopausal hormones.

In addition, a stratified analysis was performed to assess the extent to which obesity, physical activity, smoking status, and family history of diabetes influenced the outcome.

In short, this was a very rigorous and well-controlled study.

Do Whole Grains Keep Diabetes Away?

Whole GrainsTotal whole grain consumption was divided into five groups ranging from 2 servings per day to < 0.1 serving per day. When participants with the highest whole grain intake were compared to those with the lowest whole grain intake:

  • Whole grain consumption was associated with a 29% lower risk of developing type 2 diabetes.
    • The association between whole grain consumption and reduced risk of developing type 2 diabetes was stronger for lean individuals (45% reduction in risk) than for overweight (34% reduction in risk) or obese individuals (23% reduction in risk).
    • The association between whole grain consumption and reduced risk of developing type 2 diabetes was not affected by physical activity, smoking status, or family history of diabetes.

When they looked at the entire range of whole grain intake among participants in the study:

  • The risk reduction for developing type 2 diabetes was nonlinear.
    • The greatest portion of risk reduction (30% decreased risk) occurred between 0 and 2 servings/day.
    • However, the reduction in risk continued to decrease at a slower rate up to 4.5 servings/day (38% decreased risk), the highest intake recorded for participants in this study.

When they looked at the most frequently consumed whole grain foods and compared the risk of developing type 2 diabetes for participants consuming one or more servings per day compared with less than 1 serving per month:

  • People consuming whole grain cold breakfast cereals were 19% less likely to develop type 2 diabetes.
  • People consuming whole grain breads were 21% less likely to develop type 2 diabetes.
  • People consuming popcorn were 8% more likely to develop type 2 diabetes.

Once again, the risk reduction was nonlinear.

  • For whole grain cold breakfast cereals risk reduction plateaued at around 0.5 servings per day.
  • For whole grain breads the greatest portion of risk reduction occurred at around 0.5 servings per day (17% decreased risk), but the reduction in risk continued to decrease at a slower rate up to 4 servings/day (28% decreased risk).
  • For popcorn, the risk reduction curve was non-linear. There was a slight, non-significant, decrease in risk at about 0.2 servings per day, followed by a steady increase in risk up to 1.75 servings per day (24% increased risk).

When they looked at less frequently consumed whole grain foods and compared the risk of developing type 2 diabetes for participants consuming two or more servings per week compared with less than 1 serving per month:

  • People consuming oatmeal were 21% less likely to develop type 2 diabetes.
  • People consuming brown rice were 12% less likely to develop type 2 diabetes.
  • People consuming added bran were 15% less likely to develop type 2 diabetes.

There were not enough people consuming these whole grains for the investigators to determine how many servings were optimal.

The authors concluded, “Higher consumption of total whole grains and several commonly eaten whole grain foods, including whole grain breakfast cereal, oatmeal, whole grain bread, brown rice, and added bran, was significantly associated with a lower risk of type 2 diabetes. These findings provide further support for the current recommendations of increasing whole grain consumption as part of a healthy diet for the prevention of type 2 diabetes.”

Are Whole Grains Healthy?

Question MarkThis is a very impressive study. As described above, it is a large (194,784 participants), long lasting (24 years), and well-designed study. With this data in mind, we can answer several important questions.

Are Whole Grains Healthy?

This study explodes the myth that you should avoid whole grains if you want to prevent diabetes. Instead, the study shows that whole grain consumption decreases your risk of developing type-2 diabetes.

I recently reviewed another large, well-designed study showing that whole grain consumption reduces your risk of dying from heart disease, cancer, and all causes combined.

So, clearly whole grains are good for you. They should be an important part of your diet.

Which Whole Grains Are Healthy?

According to this study, whole grain breakfast cereals, whole grain breads, oatmeal, brown rice, and bran are all healthy. All of them significantly reduce your risk of developing type 2 diabetes. Other whole grains are likely to be healthy too, but Americans consume so little of them, they could not be analyzed in this study.

However, there are some caveats:

  • You have to read labels carefully. Unless it says “100% whole grain”, it probably contains more refined grains than whole grains.
    • Yes, food manufacturers are intentionally deceptive. Who knew?
  • You have to look at the food, not just “whole grain” on the label.
    • It is hard to imagine, but Dr. Kellogg originally created breakfast cereals as health food. However, today many “whole grain” cereals are loaded with sugar and artificial ingredients. They are highly processed foods that are anything but healthy.
    • The case of popcorn is a perfect example. Popcorn is loaded with fiber. It should reduce your risk of diabetes. However, in this study it increased the risk of diabetes. That’s because 70% of the popcorn that Americans consume is purchased either pre-popped or ready to pop. It contains unhealthy ingredients like salt, butter, sugar, trans fats, and artificial flavors. It is a highly processed food. Air popped popcorn without the added ingredients is probably very healthy.

Why Are Whole Grains Healthy?

Dr. Strangelove and his buddies have told you to avoid all grains because they contain carbohydrates that are converted to sugar. That is good advice for refined grains. Not only are they rapidly converted to sugar. But they are also found in highly processed foods along with sugar, fat, and a witch’s brew of chemicals.

However, whole grains are different. Yes, whole grains are carbohydrate-rich foods, and the carbohydrate is converted to sugar during digestion. But:

  • They also contain fiber, which slows the digestion of the carbohydrate and delays the absorption of the sugar released during digestion.
  • The carbohydrate is trapped in a cellular matrix, which must be digested before the carbohydrate can be released.

In addition:

  • Whole grains contain nutrients and phytonutrients not found in refined grains.
  • The fiber in whole grains supports the growth of friendly bacteria in the gut.

How Many Whole Grain Foods Should I Be Eating?

This study found that you get the biggest “bang for your buck” when you go from 0 to around 2 servings per day of whole foods.

  • If you aren’t fond of whole grain foods, that is good news. It is also in line with USDA recommendation that half the grains we eat should be whole grains. You don’t need to eat whole grains with every meal.
  • If you are a purist, you can reduce your diabetes risk even more by increasing your whole grain intake up to at least 4.5 servings per day, the highest intake measured in this study.

Are Low Carb Diets Healthy?

Low carb diets may be effective for short term weight loss, but there is no evidence that they are healthy long term. And, because they cut out one or more food groups many experts feel they are likely to be unhealthy long term.

My advice is to forget “low carb” and focus on “healthy carb” instead.

  • Eliminate refined carbs and the highly processed foods they are found in.
  • Include fruits, whole grains, and beans as part of your diet. They are high carbohydrate foods, but, as this and other studies have shown, the carbohydrates in those foods are healthy carbs.

The Bottom Line

Low carb enthusiasts tell you to eliminate whole grains from your diet if you want to reduce your risk of developing diabetes. Is this true? Is it good advice?

A recent study put this advice to the test. It was a large (194,784 participants), long lasting (24 years), and well-designed study. Here is what the study found.

When participants with the highest whole grain intake were compared to those with the lowest whole grain intake:

  • Whole grain consumption was associated with a 29% lower risk of developing type 2 diabetes.

When they looked at the entire range of whole grain intake among participants in the study:

  • The risk reduction for developing type 2 diabetes was nonlinear.
  • The greatest portion of risk reduction (30% decreased risk) occurred between 0 and 2 servings/day.
  • But the reduction in risk continued to decrease at a slower rate up to 4.5 servings/day (38% decreased risk), the highest intake recorded for participants in this study.

When they looked at individual foods, whole grain breakfast cereals, whole grain bread, oatmeal, brown rice, and added bran all reduced diabetes risk.

The authors concluded, “Higher consumption of total whole grains and several commonly eaten whole grain foods, including whole grain breakfast cereal, oatmeal, whole grain bread, brown rice, and added bran, was significantly associated with a lower risk of type 2 diabetes. These findings provide further support for the current recommendations of increasing whole grain consumption as part of a healthy diet for the prevention of type 2 diabetes.”

For more details about this study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Which Diets Are Best In 2021?

Which Diet Should You Choose?

Emoticon-BadMany of you started 2021 with goals of losing weight and/or improving your health. In many cases, that involved choosing a new diet. That was only 2 months ago, but it probably feels like an eternity.

For many of you the “bloom” has gone off the new diet you started so enthusiastically in January.

  • Perhaps the diet isn’t working as well as advertised…
  • Perhaps the diet is too restrictive. You are finding it hard to stick with…
  • Perhaps you are always hungry or constantly fighting food cravings…
  • Perhaps you are starting to wonder whether there is a better diet than the one you chose in January…
  • Perhaps you are wondering whether the diet you chose is the wrong one for you…

If you are rethinking your diet, you might want to know which diets the experts recommend. Unfortunately, that’s not as easy as it sounds. The diet world has become just as divided as the political world.

Fortunately, you have an impartial resource. Each year US News & World Report invites a panel of experts with different points of view to evaluate popular diets. They then combine the input from all the experts into rankings of the diets in various categories.

If you are still searching for your ideal diet, I will summarize the US News & World Report’s “Best Diets In 2021”. For the full report, click on this link.

How Was This Report Created?

Expert PanelUS News & World Report recruited panel of 25 nationally recognized experts in diet, nutrition, obesity, food psychology, diabetes, and heart disease to review the 39 most popular diets.  They rated each diet in seven categories:

  • How easy it is to follow.
  • Its ability to produce short-term weight loss.
  • Its ability to produce long-term weight loss.
  • its nutritional completeness.
  • Its safety.
  • Its potential for preventing and managing diabetes.
  • Its potential for preventing and managing heart disease.

They converted the experts’ ratings to scores 5 (highest) to 1 (lowest). They then used these scores to construct nine sets of Best Diets rankings:

  • Best Diets Overall combines panelists’ ratings in all seven categories. However, all categories were not equally weighted. Short-term and long-term weight loss were combined, with long-term ratings getting twice the weight. Why? A diet’s true test is whether it can be sustained for years. And safety was double counted because no diet should be dangerous.
  • Best Commercial Diets uses the same approach to rank 15 structured diet programs that require a participation fee or promote the use of branded food or nutritional products.
  • Best Weight-Loss Diets was generated by combining short-term and long-term weight-loss ratings, weighting both equally. Some dieters want to drop pounds fast, while others, looking years ahead, are aiming for slow and steady. Equal weighting accepts both goals as worthy.
  • Best Diabetes Diets is based on averaged diabetes ratings.
  • Best Heart-Healthy Diets uses averaged heart-health ratings.
  • Best Diets for Healthy Eating combines nutritional completeness and safety ratings, giving twice the weight to safety. A healthy diet should provide sufficient calories and not fall seriously short on important nutrients or entire food groups.
  • Easiest Diets to Follow represents panelists’ averaged judgments about each diet’s taste appeal, ease of initial adjustment, ability to keep dieters from feeling hungry and imposition of special requirements.
  • Best Plant-Based Diets uses the same approach as Best Diets Overall to rank 12 plans that emphasize minimally processed foods from plants.
  • Best Fast Weight-Loss Diets is based on short-term weight-loss ratings.

Which Diets Are Best In 2021?

The word WInner in white letters surrounded by a burst of colorful stars in 3d

Are you ready? If this were an awards program I would be saying “Envelop please” and would open the envelop slowly to build suspense.

However, I am not going to do that. Here are the top 5 and bottom 5 diets in each category (If you would like to see where your favorite diet ranked, click on this link). [Note: I excluded commercial diets from this review.]

Best Diets Overall 

The Top 5: 

#1: Mediterranean Diet

#2: DASH Diet (This diet was designed to keep blood pressure under control, but you can also think of it as an Americanized version of the Mediterranean diet.)

#3: Flexitarian Diet (A flexible semi-vegetarian diet).

#4: Mayo Clinic Diet

#5: MIND Diet (This diet is a combination of Mediterranean and DASH but is specifically designed to reduce cognitive decline as we age.)

The Bottom 5: 

#35: Modified Keto Diet

#36: Whole 30 Diet

#37: GAPS Diet (A diet designed to improve gut health).

#38: Keto Diet

#39: Dukan Diet

Best Weight-Loss DietsWeight Loss

The Top 5: 

#1: Flexitarian Diet

#2: Vegan Diet

#3: Volumetrics Diet (A diet based on the caloric density of foods).

#4: Mayo Clinic Diet

#5: Ornish Diet

The Bottom 5: 

#35: Fertility Diet

#36: Whole 30 Diet

#37: Alkaline Diet

#38: AIP Diet (A diet designed for people with autoimmune diseases)

#39: GAPS Diet

Best Diabetes Diets

The Top 5: 

#1: Flexitarian Diet

#2: Mediterranean Diet

#3: DASH Diet

#4: Mayo Clinic Diet

#5: Vegan Diet

The Bottom 5: 

#35: The Fast Diet

#36: AIP Diet

#37: GAPS Diet

#38: Whole 30 Diet (A diet designed for people with autoimmune diseases)

#39: Dukan Diet

strong heartBest Heart-Healthy Diets 

The Top 5: 

#1: DASH Diet

#2: Mediterranean Diet

#3: Ornish Diet (A diet based on the caloric density of foods).

#4: Flexitarian Diet

#5: Vegan Diet

The Bottom 5: 

#35: Keto Diet

#36: AIP Diet

#37: Whole 30 Diet

#38: Modified Keto Diet

#39: GAPS Diet

Best Diets for Healthy Eating

The Top 5: 

#1: DASH Diet

#2: Mediterranean Diet

#3: Flexitarian Diet

#4: TLC Diet (A diet designed to promote heart health)

#5: MIND Diet

The Bottom 5: 

#35: Atkins Diet

#36: Raw Food Diet

#37: Modified Keto Diet

#38: Dukan Diet

#39: Keto Diet 

Easiest Diets to FollowEasy

The Top 5: 

#1: Mediterranean Diet

#2: Flexitarian Diet

#3: MIND Diet

#4: DASH Diet

#5: Fertility Diet

The Bottom 5: 

#35: Keto Diet and Modified Keto Diet (tie)

#36: Whole 30 Diet

#37: Dukan Diet

#38: GAPS Diet

#39: Raw Foods Diet 

Best Fast Weight-Loss Diets

The Top 5 (Excluding Commercial Diets): 

#1: Atkins Diet

#2: Biggest Loser Diet

#3: Keto Diet

#4: Raw Food Diet

#5: Volumetrics Diet

Which Diets Are Best For Rapid Weight Loss?

Happy woman on scaleLet me start with some general principles:

#1: If you are looking for rapid weight loss, any whole food restrictive diet will do.

  • The Atkins and keto diets are meat heavy, low carb diets. They restrict fruits, some vegetables, grains, and most legumes.
  • The Biggest Loser diet relies on restrictive meal plan and exercise programs.
  • The restrictions of the raw food diet are obvious.
  • The volumetrics diet restricts foods with high caloric density.
  • The vegan diet, which ranks #7 on this list, is a very low fat diet that eliminates meat, dairy, eggs, and animal fats.
  • I did not include commercial diets that rated high on this list, but they are all restrictive in one way or another.

#2: Restrictive diets ultimately fail.

  • The truth is 90-95% of people who lose weight quickly on a restrictive diet regain most of that weight in the next two years. The pounds come back and often bring their friends along as well. Many people regain more weight than they lost. This is the famous “Yo-Yo Effect”.
  • If dieters paid for one of the commercial diets, they may as well have burned their money.
  • When I talk with people about weight loss, many of them tell me the Atkins diet is the only one they can lose weight on. That would be impressive if they were at a healthy weight, but most are not. They are overweight. I am starting to see the same thing from overweight people who have used the keto diet to lose weight and have regained their weight.

#3: We should ask what happens when we get tired of restrictive diets and add back some of your favorite foods.

  • If you lose weight on a vegan diet and add back some of your favorite foods, you might end up with a semi-vegetarian diet. This is a healthy diet that can help you maintain your weight loss.
  • If you lose weight on the Atkins or keto diets and add back some of your favorite foods, you end up with the typical American diet – one that is high in both fat and carbs. This is not a recipe for long-term success.
  • Long term weight loss is possible if you transition to a healthy diet after you have lost the weight. In a recent article in “Health Tips From The Professor” I wrote about an organization called the National Weight Control Registry. These are people who have been successful at keeping the weight off. For purposes of this discussion, two points are important.
  • They lost weight on every possible diet.
  • They kept the weight off by following a healthy reduced calorie, low fat diet. (For what else they did, click here).

Which Diet Should You Choose?

Which Diet Is BestWith rapid weight loss out of the way, let’s get back to the question, “Which Diet Should You Choose?” My recommendations are:

  • Choose a diet that fits your needs. That is one of the things I like best about the US News & World Report ratings. The diets are categorized. If your main concern is diabetes, choose one of the top diets in that category. If your main concern is heart health… You get the point.
  • Choose diets that are healthy and associated with long term weight loss. If that is your goal, you will notice that primarily plant-based diets top these lists. Meat-based, low carb diets like Atkins and keto are near the bottom of the lists.
  • Choose diets that are easy to follow. The less-restrictive primarily plant-based diets top this list – diets like Mediterranean, DASH, MIND, and flexitarian.
  • Choose diets that fit your lifestyle and dietary preferences. For example, if you don’t like fish and olive oil, you will probably do much better with the DASH or flexitarian diet than with the Mediterranean diet.
  • Finally, focus on what you have to gain, rather than on foods you have to give up.
    • On the minus side, none of the diets include sodas, junk foods, and highly processed foods. Teose foods should go on your “No-No” list. Sweets should be occasional treats and only as part of a healthy meal. Meat, especially red meat, should become a garnish rather than a main course.
    • On the plus side, primarily plant-based diets offer a cornucopia of delicious plant foods you probably didn’t even know existed. Plus, for any of the top-rated plant-based diets, there are websites and books full of mouth-watering recipes. Be adventurous.

The Bottom Line 

For many of you the “bloom” has gone off the new diet you started so enthusiastically in January. If you are rethinking your diet, you might want to know which diets the experts recommend. Unfortunately, that’s not as easy as it sounds. The diet world has become just as divided as the political world.

Fortunately, you have an impartial resource. Each year US News & World Report invites a panel of experts with different points of view to evaluate popular diets. They then combine the input from all the experts into rankings of the diets in various categories. In the article above I summarize the US News & World Report’s “Best Diets In 2021”.

There are probably two questions at the top of your list.

#1: Which diets are best for rapid weight loss? Here are some general principles:

  • If you are looking for rapid weight loss, any whole food restrictive diet will do.
  • Restrictive diets ultimately fail.
  • We should ask what happens when we get tired of restrictive diets and add back some of our favorite foods.
  • Long term weight loss is possible if you transition to a healthy diet after you have lost the weight.

#2: Which diet should you choose? Here the principles are:

  • Choose a diet that fits your needs.
  • Choose diets that are healthy and associated with long term weight loss.
  • Choose diets that are easy to follow.
  • Choose diets that fit your lifestyle and dietary preferences.
  • Finally, focus on what you have to gain, rather than on foods you have to give up.

For more details on the diet that is best for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

What Do The US Dietary Guidelines Say About Supplementation?

What Do The US Dietary Guidelines Say About Your Diet?

Author: Dr. Stephen Chaney

US Dietary Guidelines 2020-2025Science is always changing, and nutritional science is no different. As we learn more, our concept of the “ideal diet” is constantly evolving. Because of that, the USDA and the US Department of Health & Human Services produce a new set of Dietary Guidelines for Americans every 5 years.

The 2020-2025 Dietary Guidelines for Americans have just been released. As usual, the process started with a panel of 20 internationally recognized scientists who produced a comprehensive report on the current state of nutritional science and made recommendations for updated dietary guidelines. After a period of public comment, the dietary guidelines were published.

There were two new features of the 2020-2025 Guidelines:

  • They provided dietary guidelines for every life stage from 6 months of life to adults over 60.
  • The guidelines also addressed personal preferences, cultural traditions, and budgetary concerns in so that each of us can develop a healthy diet that fits our lifestyle.

What Do The US Dietary Guidelines Say About Your Diet?

Here are the 2020-2025 Guidelines in a nutshell:healthy foods

  • Follow a healthy dietary pattern at every life stage.
  • Customize and enjoy nutrient-dense food and beverage choices to reflect personal preferences, cultural traditions, and budgetary considerations.
  • Focus on meeting food group needs with nutrient-dense foods and beverages and stay within calorie limits. They went on to say, “A healthy dietary pattern consists of nutrient-dense forms of foods and beverages across all food groups [emphasis mine], in recommended amounts, and within calorie limits.”

They said, “the core elements that make up a healthy dietary pattern include:”

    • Vegetables of all types – dark green, red, and orange vegetables; beans, peas, and lentils; starchy vegetables; and other vegetables.
    • Fruits – especially whole fruits.
    • Grains – at least half of which are whole.
    • Dairy – including fat-free or low-fat milk, yogurt, and cheese; lactose-free versions; and fortified soy beverages and soy yogurt as alternatives. [Other plant-based milk and yogurt foods were not recommended because they do not provide as much protein as dairy. So, they were not considered equivalent foods.]
    • Protein foods – including lean meats, poultry, and eggs; seafood; beans, peas, and lentils; and nuts, seeds, and soy products.
    • Oils – including vegetable oils and oils in food, such as seafood and nuts.
  • Limit foods and beverages higher in added sugars, saturated fat, and sodium; and limit No Fast Foodalcoholic beverages. Their specific recommendations are:
    • Added sugars – less than 10% of calories/day starting at age 2. Avoid foods and beverages with added sugars for those younger than 2.
    • Saturated fat – Less than 10% of calories starting at age 2.
    • Sodium – Less than 2,300 mg per day – even less for children younger than 14.
    • Alcoholic beverages – Adults of legal drinking age can choose not to drink, or to drink in moderation by limiting intake to 2 drinks or less in a day for men and 1 drink or less in a day for women, when alcohol is consumed. Drinking less is better for health than drinking more. There are some adults who should not drink alcohol, such as women who are pregnant.

For more details, read the 2020-2025 Dietary Guidelines for Americans.

The Dark Side Of The US Dietary Guidelines

Darth VaderThe US Dietary Guidelines point Americans in the right direction, but they are never as strong as most nutrition experts would like. The 2025 Dietary Guidelines are no exception. They have two major limitations:

#1: The food industry has watered down the guidelines. This happens every time a new set of guidelines are released. The food and beverage lobbies provide their input during the public comment period. And because they fund a significant portion of USDA research, their input carries a lot of weight. Here are the 3 places where they altered the recommendations of the scientific panel:

  • The scientific panel recommended that Americans decrease the intake of added sugar from 13% of daily calories to 6%. The final dietary guidelines recommended reducing sugar to 10% of daily calories.
  • The scientific panel recommended that both men and women limit alcoholic drinks to one a day. The final dietary guidelines recommended men limit alcoholic drinks to two a day.
  • The scientific panel included these statements in their report:
    • “Dietary patterns characterized by higher intake of red and processed meats, sugar-sweetened foods and beverages, and refined grains are…associated with detrimental health outcomes.”
    • “Replacing processed or high fat-meats…with seafood could help lower intake of saturated fat and sodium, nutrients that are often consumed in excess of recommended limits.”
    • “Replacing processed or high-fat meats with beans, peas, and lentils would have similar benefits.”

These statements are included in the final report, but they are buried in portions of the report that most people are unlikely to read. The summary that most people will read recommends shifts in protein consumption to “add variety” to the diet.

#2: The guidelines do not address sustainability and do not explicitly promote a shift to more Planetary Dietplant-based diets. Again, this was based on input from food lobby groups who argued that sustainability has nothing to do with nutrition.

If you are concerned about climate change and the degradation of our environment caused by our current farming practices, this is a significant omission.

I have covered this topic in a recent issue of “Health Tips From the Professor”. Here is a brief summary:

  • In 2019 a panel of international scientists was asked to conduct a comprehensive study on our diet and its effect on both our health and our environment.
  • The scientific panel carefully evaluated diet and food production methods and asked three questions:
    • Are they good for us?
    • Are they good for the planet?
    • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.
  • They developed dietary recommendations popularly known as the “Planetary Diet”. Here are the characteristics of the planetary diet.
    • It starts with a vegetarian diet. Vegetables, fruits, beans, nuts, soy foods, and whole grains are the foundation of the diet.
    • It allows the option of adding one serving of dairy a day.
    • It allows the option of adding one 3 oz serving of fish or poultry or one egg per day.
    • It allows the option of swapping seafood, poultry, or egg for a 3 oz serving of red meat no more than once a week. If you want a 12 oz steak, that would be no more than once a month.

Unless you are a vegan, this diet is much more restrictive than you are used to. However, if you, like so many Americans believe that climate change is an existential threat, I would draw your attention to one of the concluding statements from the panel’s report.

  • “Reaching the Paris Agreement of limiting global warming…is not possible by only decarbonizing the global energy systems. Transformation to healthy diets from sustainable food systems is essential to achieving the Paris Agreement.”

In other words, we can do everything else right, but if we fail to change our diet, we cannot avoid catastrophic global warming.

What Do The US Dietary Guidelines Say About Supplementation?

MultivitaminsThe authors of the 2020-2025 US Dietary Guidelines have relatively little to say about supplementation. However:

  • They list nutrients that are of “public health concern” for each age group. Nutrients of public health concern are nutrients that:
    • Are underconsumed in the American diet.
    • Are associated with health concerns when their intake is low.
  • They state that “dietary supplements may be useful in providing one or more nutrients that otherwise might be consumed in less than recommended amounts.”
  • They recommend specific supplements for several age groups.

Here are their nutrients of public health concern and recommended supplements for each age group:

#1: General population.

  • Nutrients of public health concern are calcium, dietary fiber, and vitamin D. They state that supplementation may be useful for meeting these needs.

#2: Breast Fed Infants.

  • Supplementation with 400 IU/day of vitamin D is recommended shortly after birth.

#3: Vegetarian Toddlers.

  • Iron and vitamin B12 are nutrients of concern.

#4: Children & Adolescents.

  • Calcium and vitamin D are nutrients of concern. Dairy and/or fortified soy alternatives are recommended to help meet these needs.
  • Iron, folate, vitamin B6, vitamin B12, and magnesium are also nutrients of concern for adolescent females.

#5: Adults (Ages 19-59).

  • 30% of men and 60% of women do not consume enough calcium and 90% of both men and women do not get enough vitamin D.

#6: Pregnant & Lactating Women:

  • Calcium, vitamin D, and fiber are nutrients of concern for all women in this age group.
  • In addition, women who are pregnant have special needs for folate/folic acid, iron, iodine, and vitamin D.
  • Women who are pregnant or thinking of becoming pregnant should take a daily prenatal vitamin and mineral supplement to meet folate/folic acid, iron, iodine, and vitamin D needs during pregnancy. They go on to say that many prenatal supplements do not contain iodine, so it is important to read the label.
  • All women who are planning or capable of pregnancy should take a daily supplement containing 400 to 800 mcg of folic acid.

#7: Older Adults (≥ 60).

  • Nutrients of concern for this age group include calcium, vitamin D, fiber, protein, and vitamin B12.
  • About 50% of women and 30% of men in this age group do not get enough protein in their diet.

My Perspective:

The US Dietary Guidelines use foods of public health concern as the only basis for recommending Supplementation Perspectivesupplementation. I prefer a more holistic approach that includes increased needs, genetic predisposition, and preexisting diseases as part of the equation (see the diagram on the right). I have discussed this concept in depth in a previous issue of “Health Tips From The Professor”.

I have also taken this concept and made supplement recommendations for various health goals in a free eBook called “Your Design For Healthy Living”.

Some people may feel I should have included more supplements in my recommendations. Others may feel I should have included fewer supplements in my recommendations. No list pf recommend supplements is perfect, but I have tried to include those supplements supported by good scientific evidence in my recommendations.

The Bottom Line 

The USDA and Department of Health & Human Services have just released the 2020-2025 US Dietary Guideline. In the article above I have summarized:

  • Their recommendations for a healthy diet.
  • Their recommendations for supplementation.
  • The dark side of the US Dietary Guidelines.

For more details, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Do Antioxidants Reduce Diabetes Risk?

What Diet Is Best For Reducing Your Risk Of Diabetes?

ConfusionI don’t need to tell you that nutrition is confusing. The headlines change day to day. One day antioxidants are good for you. The next day they are worthless. What are you to believe?

That is why I knew you would be skeptical when you saw recent headlines saying things like, “Antioxidants reduce your risk of diabetes” or “An antioxidant-rich diet may prevent diabetes”. You are probably waiting for the other shoe to drop.

You are waiting for the next headline telling you to ignore the previous headlines.

That is why I decided to analyze the study (FM Mancini et al, Diabetologia, 61: 308-316, 2018) behind the headlines and tell you whether the headlines were true or false. More importantly, I wanted to put the study into perspective so you could apply the findings to your life.

How Was The Study Done?

Clinical StudyThe data for this paper came from the Interaction of Genetic and Lifestyle Factors on the Incidence of Type 2 Diabetes (InterAct) study. French women born between 1925 and 1950 were enrolled in the study beginning in 1990.

Women were excluded from the study if they had pre-existing cardiovascular disease, diabetes, or cancer.

In June of 1993 a very extensive dietary questionnaire was mailed to all participants. The antioxidant capacity of each of the foods in the diet was estimated using an existing database, and the total antioxidant content of each woman’s diet was calculated.

A total of 64,223 women (average age = 52) completed the questionnaire and were followed for 15 years. During that time 1751 of the women developed type 2 diabetes.

The study correlated the total antioxidant content of the diet with the risk of developing type 2 diabetes. Coffee was excluded from the analysis because the antioxidants found in coffee are high molecular weight compounds, and it is not clear how well they are absorbed.

The major sources of antioxidants in the French diet were fruits (23%), vegetables (19%), wine (15%), tea (10%), and chocolate (2%). Whole grains and beans are also good sources of antioxidants, but the French (and Americans) don’t eat enough of them to influence their total antioxidant intake.

In case you were wondering why wine and chocolate were among the five top sources of antioxidants, remember this is the French diet we are talking about.

Do Antioxidants Reduce Diabetes Risk?

Diabetes and healthy die The authors of the study divided the women into 5 groups (quintiles) based on the antioxidant content of their diets. Quintile one had the lowest antioxidant intake, and quintile five had the highest antioxidant intake.

Compared to the women in quintile one (lowest antioxidant intake), the risk of developing type 2 diabetes was decreased by:

  • 15% for women in quintile two.
  • 30% for women in quintile three.
  • 38% for women in quintile four.
  • 39% for women in quintile five (highest antioxidant intake).
  • As you might guess from the data above, there was an inverse association between total antioxidant content of the diet and type 2 diabetes up until somewhere between the third and fourth quintiles.
  • Above that antioxidant level, the relationship between dietary antioxidant content and risk of developing type 2 diabetes plateaued.

The authors concluded, “Our findings suggest that the total antioxidant capacity of the diet may play a role in reducing the risk of type 2 diabetes in middle-aged women. As type 2 diabetes represents a high disease burden worldwide, our results may have important public health implications.”

What Diet Is Best For Reducing Your Risk Of Type 2 Diabetes?

While most of the headlines talked about the effect of antioxidant intake on the risk of developing type 2 diabetes, we need to remember that the study was done with antioxidant-rich foods. That raises 3 important questions.

#1: Is it the antioxidants or the foods that decrease the risk of developing type 2 diabetes?

Diabetes-&-Vitamin-CThis was a diet rich in fruits, vegetables, and tea with moderate amounts of wine and chocolate. Although they didn’t make it to the top 5 in this study, whole grains and beans are also a good source of dietary antioxidants. In short, this was a very healthy diet.

That represents a complicating factor. For example, fruits and vegetables are also good sources of non-antioxidant phytonutrients that appear to have health benefits. They are also a good source of fiber and the healthy gut bacteria that eat the fiber.

In short, this study shows that healthy foods reduce the risk of developing type 2 diabetes. Since oxidative stress is thought to play a role in the development of diabetes, it is logical that antioxidants in these foods may help prevent diabetes. However, in reality, we don’t know how much of the risk reduction is due to the antioxidant content of the foods and how much is due to other components of the foods.

#2: Is it healthy foods that decrease the risk of type 2 diabetes, or is it due to decreased intake of unhealthy foods?

food choiceThe skeptic in me wants to ask, “Is the diabetes risk reduction due to the healthy foods included in the diet or does it derive from the fact that those foods displaced unhealthy foods from the diet?” It is also legitimate to ask whether people who eat healthier foods also followed a healthier lifestyle.

Fortunately, the data from this study puts those questions to rest. Compared to women in the lowest quintile of antioxidant intake, women in the highest quintile of antioxidants intake from diet:

  • Drank more sugar-sweetened and artificially sweetened beverages.
  • Ate more processed meat.
  • Ate more calories.
  • Smoked more.
  • Were just as likely to be overweight.

These women were more physically active, but in other ways their diet and lifestyle were no better than women with much less antioxidant intake.

However, we do need to remember that these are French women. Their overall diet and lifestyle is much better than American women. For example, at their worst:

  • 30% were overweight or obese compared to >60% for American women.
  • Intake of processed meat was less than ½ serving/day.
  • Intake of sugar-sweetened beverages was less than 1 ounce/day and intake of artificially sweetened beverages was 1.3 ounces/day.

#3: How much healthy foods do your need to include in your diet to reduce the risk of type 2 diabetes?

fruits and vegetablesThe fact that the beneficial effect of adding antioxidant-rich foods to your diet reduced the risk of developing type 2 diabetes up to a point and then plateaued has important implications. It means you don’t need to be a vegan to reduce your risk of type 2 diabetes. You just need to include enough healthy foods in your diet.

“How much healthy foods”, you might ask. If we look at the point at which the benefit of eating antioxidant-rich foods plateaued in this study, the women were eating:

  • 5-6 servings of fresh fruits and vegetables per day.
  • 4 cups of tea/day.
  • 7 pieces of chocolate/day.
  • 1 glass of wine/day.

If you are an American who is consuming less tea, chocolate, and wine than the French, you will probably want to aim for 6 or more servings of fresh fruits and vegetables per day and include whole grains and beans in your diet.

In a previous issue of “Health Tips From the Professor” I reviewed a study that looked at the optimal intake of fruits and vegetables for various other diseases. That study reported:

  • 10 servings per day is optimal for reducing the risk of heart disease, stroke, and premature death.
  • 6 servings per day is optimal for reducing the risk of cancer.

This study suggests 6 servings of fruits and vegetable per day is likely to also be optimal for reducing the risk of developing type 2 diabetes.

The bad news is that the average American eats one serving of fruit and less than 2 servings of vegetables a day. The good news is that each added serving of fruits and vegetables reduces your risk of disease and premature death. The same is probably true for whole grains and beans, but they weren’t specifically included in these studies.

What About Supplementation?

vitamin COf course, some of you will be tempted to say, “Changing my diet is hard. I’ll just take antioxidant supplements.” Will that work. If we are talking about individual antioxidant supplements, the answer is a clear, “No”. Numerous clinical studies have shown that.

However, one study looked at a holistic approach to supplementation and found that it significantly decreased the risk of developing type 2 diabetes over a 20-year period. That is encouraging, but you need to know that the people in that study were not just consuming antioxidant supplements. They were also consuming:

  • Supplements containing B vitamins, calcium, magnesium, and trace minerals.
  • Plant-based protein supplements that replaced some of the animal protein in their diet.
  • Omega-3 supplements.
  • Probiotic supplements.

So, just as was true for the diet study discussed above, antioxidant supplements may be beneficial in reducing the risk of developing type 2 diabetes. However, it is not possible to separate the benefits of antioxidant supplements from the other supplements included in the study.

The Bottom Line

You may have seen recent headlines claiming, “Antioxidants reduce your risk of diabetes”. The study behind those headlines was actually looking at the effect of antioxidant-rich foods like fruits and vegetables at decreasing the risk of developing type 2 diabetes.

The study did show that increasing the amount of antioxidant-rich foods in your diet decreases your risk of developing type 2 diabetes.

Since oxidative stress is thought to play a role in the development of diabetes, it is logical that antioxidants in those foods may help prevent diabetes. However, in reality we don’t know how much of the risk reduction is due to the antioxidant content of the foods and how much is due to the phytonutrient and fiber content of the foods.

There was an inverse association between total antioxidant content of the diet and type 2 diabetes up until somewhere between the 5 and 6 servings per day of fresh fruits and vegetables. At that point. the beneficial effect of eating antioxidant-rich foods plateaued. Eating 6 servings per day of fresh fruits and vegetables appears to be optimal for reducing the risk of developing type 2 diabetes.

To put that into perspective, a previous study that looked at the optimal intake of fruits and vegetables for various other diseases reported:

  • 10 servings per day is optimal for reducing the risk of heart disease, stroke, and premature death.
  • 6 servings per day is optimal for reducing the risk of cancer.

The bad news is that the average American eats one serving of fruit and less than 2 servings of vegetables a day. The good news is that each added serving of fruits and vegetables reduces your risk of disease and premature death. The same is probably true for whole grains and beans, but they weren’t specifically included in these two studies.

Of course, if you really wish to prevent or reverse type 2 diabetes, a holistic approach including weight control, exercise, diet, and supplementation is best.

For more details, including a more detailed discussion of supplementation, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 

Finally, you should also never think of supplementation as a replacement for a healthy diet. If you wish to reduce your risk of developing type 2 diabetes, I recommend a holistic approach that includes weight control, exercise, diet, and supplementation.

Does Eating Plant Protein Help You Live Longer?

Are Whole Grains Heart Healthy?

protein and heart disease nuts and seedsThe diet wars continue. Dr. Strangelove and his colleagues are still trying to convince you that you can eat all the red meat you want. It is those deadly whole grains, beans, and fruits you need to avoid.

However, as the benefits of primarily plant-based diets continue to accumulate, it is becoming harder for them to maintain these preposterous claims.

For example, several recent studies have shown that replacing animal protein with plant protein in your diet results in better health.

  • The Iowa Women’s Health Study found that plant protein substitution for animal protein is associated with reduced risk of dying from heart disease.
  • The Nurse’s Health Study and Health Professionals Follow-up Study found that greater plant protein intake was associated with reduced risk of dying from heart disease and reduced risk of dying from all causes.
  • The Japan Public Health Center-Based Prospective Cohort Study found a reduced risk of dying from heart disease, cancer, and all causes with substitution of plant protein for red meat protein.

These were all very large studies in which populations were followed for long periods of time. You might be thinking that with such overwhelming evidence no further studies are needed.

However, these studies did not examine which plant protein sources were most beneficial and which animal protein sources were most detrimental. The study (J. Huang et al, JAMA Internal Medicine, published online July 13, 2020) I describe in today’s “Health Tips From The Professor” was designed to answer that question.

How Was The Study Done?

Clinical Study416,104 participants from the NIH-AARP Diet and Health Study were enrolled in this study in 1995 and 1996 and were followed for 16 years. At the time of enrollment, the participants filled out a comprehensive Diet History Questionnaire. The participants also completed questionnaires about their health, lifestyle, and socio-economic status.

Deaths were obtained from the Social Security Death Master File. Causes of death were obtained from the National Death Index Plus.

The basic characteristics of the study population were:

  • Gender: 57% men, 43% women.
  • Racial identification: 90% non-Hispanic white.
  • Average age 61 (range 50-71).
  • Average BMI = 27 (in the overweight range).
  • Participants were excluded from the study if they had pre-existing cancer, heart disease, stroke, or end-stage kidney disease.

In terms of protein intake:

  • Average protein intake was 15.3% of calories.
  • Plant protein contributed 40% (range 27% – 57%) to the total protein intake.
  • Animal protein contributed 60% (range = 43% to 63%) of the total protein intake.

The major sources of animal protein in the diet were:

  • Dairy products = 31.6%
  • White meat (poultry, fish, and processed white meat) = 31.3%
  • Red meat (both fresh and processed) = 30.6%
  • Eggs = 4.0%

The major sources of plant protein in the diet were:

  • Grains (bread, cereal, and pasta) = 45.8%
  • Beans and legumes = 8.0%
  • Nuts and seeds = 4.5%
  • Other plant protein (including plant protein from supplements) = 41.7%

All these protein intake figures are normal for the American diet.

I should note that beans, nuts, and seeds are among the best sources of plant protein. However, they are only a minor part of the typical American diet, so they contribute relatively little to our plant protein intake.

Does Eating Plant Protein Help You Live Longer?

In terms of overall protein intake, this study mirrored previous studies.

  • There was an inverse association between plant protein intake and premature death from heart disease, stroke, and all causes. Put another way, the more plant protein people in this study ate, the lower was their risk of premature death.

To quantify the effect, the investigators asked what happened when 3% of calories came from plant protein instead of animal protein. I recognize, however, that 3% of calories is a rather abstract concept, so let me break it down for you so you can apply it to your lives.

  • For participants in this study, protein was 15% of their total calories. That means when the investigators were talking about shifting 3% of total calories from animal protein to plant protein, they were talking about 20% of the protein in the diet coming from plant protein rather animal protein.
  • Based on the average caloric intake of participants in this study, that corresponds to 15 grams of protein for men and 12 grams of protein for women.

With that in mind, let’s look at the results:

  • Changing just 3% of calories from animal protein to plant protein:
  • Lowered the risk of premature death from all causes by 10% for both men and women.
  • Lowered the risk of premature death from cardiovascular disease by 11% for men and 12% for women.
  • Lowered the risk of premature death from stroke by 22% for men and 19% for women.

These findings are consistent with previous studies. By now, it should be apparent that primarily plant-based diets are best for your overall health. Primarily plant-based diets also appear to reduce your risk of dying prematurely from heart disease and from all other diseases combined.

The authors concluded: “This large cohort investigation showed small but significant associations between higher intake of plant protein and lower overall and cardiovascular mortality…Findings from this and previous studies provide evidence that dietary modifications in choice of protein sources may promote health and longevity.”

However, this part of the study merely confirms what other studies have shown. What makes this study unique is that it identifies which animal proteins are worst for us and which plant proteins are best for us.

Which Animal Proteins Are Least Heart Healthy?

Animal Protein FoodsLet’s start with the animal proteins (Note: To simplify a complex set of data, I am going to average the results for men and women).

  • Changing 3% of calories from egg protein to plant protein:
    • Lowered the risk of premature death from all causes by 23%.
    • Lowered the risk of premature death from cardiovascular disease by 27%.
    • To put this into perspective, 3% of calories from egg protein corresponds to around 2.5 eggs/day. So, talking about replacing 3% of calories of egg protein creates a false narrative. The average egg consumption in this study was 0.5 eggs/day and very few participants consumed even 2 eggs every day. If we make a more reasonable comparison, replacing one egg/day with an equivalent amount of plant protein:
      • Lowers the risk of premature death from all causes by 9%.
      • Lowers the risk of premature death from cardiovascular disease by 11%.
  • Changing 3% of calories from red meat protein to plant protein:
    • Lowered the risk of premature death from all causes by 14%.
    • Lowered the risk of premature death from cardiovascular disease by 12%.
    • Lowered the risk of premature death from stroke by 21%.
    • To put this into perspective, 3% of calories from red meat protein corresponds to around 2 ounces/day.
  • Changing 3% of calories from dairy protein to plant protein:
    • Lowered the risk of premature death from all causes by 8%.
    • Lowered the risk of premature death from cardiovascular disease by 11%.
    • Lowered the risk of premature death from stroke by 21%.
    • To put this into perspective, 3% of calories from dairy protein corresponds to around 1.7 8-ounce glasses of milk, 2 ounces of cheese, or 1 cup of yogurt (most yogurt “cups” sold commercially are less than an 8-ounce cup).
  • Changing 3% of calories from white meat protein to plant protein had no effect on premature death from any disease in this study. I will discuss the reasons for that below.

Are Whole Grains Heart Healthy?

Whole GrainsNow, let’s look at the flip side. What happens when you replace 3% of calories from red meat protein with various kinds of plant protein?

  • Changing 3% of calories from red meat protein to plant protein from whole grains:
    • Lowered the risk of premature death from all causes by 28%.
    • Lowered the risk of premature death from cardiovascular disease by 32%.
    • Lowered the risk of premature death from stroke by 32%.
    • To put this into perspective, 3% of calories from whole grain protein corresponds to around 2.5 slices of whole grain bread, 2 cups of oatmeal, or 2.5 cups of brown rice or whole grain pasta – or any combination of them during the day.
  • The results were similar for replacing egg protein with whole grain protein.
  • Changing 3% of calories from red meat protein or egg protein to other types of plant protein had no effect on premature death from any disease. The reasons for that will be discussed below.

The authors concluded “…this investigation showed prominent inverse associations between overall and cardiovascular mortality and the replacement of egg protein and red meat protein with plant protein, particularly for plant protein derived from bread, cereal, and pasta…”

Why Do Animal Proteins Increase Your Risk Of Premature Death?

Let me take a deep dive into the data. If you like, you can skip to “What Does This Study Mean For You?”

To help you gain a better understanding of these results, I will answer two questions for you:

  • Mechanism: What is/are the metabolic explanation(s) for these results?
  • Perspective: How can you apply this information to your own life?

Reminder: This section is for those of you who want the details. I will give the Cliff Notes summary in the section “What Does This Study Mean For You”.

EggsEggs

Mechanism:

  • The bad effect of eggs on cardiovascular mortality and all-cause mortality is thought to be almost exclusively due to their high cholesterol content.
  • On the flip side, eggs are an excellent source of low-fat animal protein and provide nutrients like choline and carotenoids that are often insufficient in the American diet.

Perspective:

  • Our bodies have a beautifully designed system for regulating blood cholesterol levels. This means under ideal conditions dietary cholesterol has very little effect on blood cholesterol levels. However, as I have pointed out in a previous issue of “Health Tips From the Professor”, conditions are often far from ideal.
  • Diet context matters. Obesity, saturated fat, and sugar all interfere with our ability to regulate blood cholesterol levels. People consuming the typical American diet, like the ones in this study, have more difficulty regulating their blood cholesterol levels and are more likely to be adversely affected by dietary cholesterol from eggs and other high-cholesterol foods.
    • Previous studies suggest that adding eggs to the typical American diet may increase risk of cardiovascular disease and premature death.
    • In contrast, adding eggs to a primarily plant-based diet, such as found in China and Japan, appears to decrease risk of heart disease and premature death.

Red Meatfatty steak

Mechanisms: The mechanism(s) associated with the bad effects of red meat are less clear. Here are the potential mechanisms discussed by the authors of this study.

  • Red meat is high in cholesterol. While many experts have downplayed the importance of dietary cholesterol in recent years, it still may be of concern in the context of the typical American diet because of our body’s inability to regulate cholesterol metabolism normally.
  • Red meat is high in saturated fat. While some experts have downplayed the importance of reducing saturated fat intake, I pointed out in a previous issue of “Health Tips From the Professor” that it depends on what the saturated fat is replaced with.
    • When saturated fats are replaced with sugar and refined carbohydrates in the typical American diet, reducing saturated fat is of no benefit.
    • When saturated fats are replaced with polyunsaturated fats in the context of a primarily plant-based diet, such as the Mediterranean diet, reducing saturated fats leads to a substantial reduction in the risk of heart disease and premature death.
  • Red meat also contains heme iron which is associated with 57% increased risk of cardiovascular disease.
  • Diets high in red meat result in populations of gut bacteria that are associated with increased risk of cardiovascular disease. This is most likely because red meat is displacing plant foods that support the growth of healthy bacteria.
  • As discussed in a recent issue of “Health Tips From the Professor”, the gut bacteria associated with red meat consumption convert the L-carnitine in red meat to a metabolite called trimethylamine N-oxide (TMAO) which appears to significantly increase the risk of cardiovascular disease.
  • Finally, a recent study suggests that foods high in sulfur-containing amino acids significantly increase risk of cardiovascular disease. However, this mechanism is not specific for red meat. White meat, beans, and legumes are also high in sulfur-containing amino acids.

Perspective:

  • While the exact mechanism(s) is/are uncertain, there is substantial evidence from multiple studies that red meat consumption increases the risk of premature death from cardiovascular disease and from all causes.
  • Grass fed beef is not a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • However, those of you who, like me, enjoy red meat should not consider this to be an absolute “red meat should never touch your lips” edict. As I have discussed in a previous issue of “Health Tips From the Professor”, the health effects of red meat are a matter of quantity and diet context.
    • If you are thinking in terms of a juicy 8-ounce steak with a baked potato and sour cream, red meat is probably not a healthy choice.
    • However, if you are thinking of 2-3 ounces of lean steak in a vegetable stir fry or a green salad, red meat may be a healthier choice.

dairy products and heart diseaseDairy: I have reported on the health risks and benefits of dairy foods in a previous issue of “Health Tips From the Professor”, so I will just give you a brief summary here.

Perspective:

  • Eating dairy foods, even high-fat dairy foods, has relatively little effect on cardiovascular disease risk in the context of the typical high-fat, high-sugar American diet.
  • Eating dairy foods, even high-fat dairy foods, in the context of a healthy plant-based diet appears to lower cardiovascular disease risk.
  • As this study suggests, moving towards a more plant-based diet by substituting some plant protein for dairy protein in the diet will also decrease your risk of cardiovascular disease

White Meat: This and previous studies suggest that white meat is less likely than red meat to increase the risk of cardiovascular disease and premature death. I have discussed the differences between red and white meat in a previous issue of “Health Tips From the Professor”. However, I can summarize the differences best here by going back to the mechanisms associated with the link between red meat and cardiovascular diseases and highlight those that do not apply to white meat.

Mechanisms:

  • Saturated fat. Many fish are much lower in saturated fat and are excellent sources of heart-healthy omega-3 fats. Chicken and turkey breast with the skin removed are also much lower in saturated fat than red meat.
  • Heme iron. Chicken breast is lower in heme iron than red meats.
  • TMAO. White meats contain 10-50 times less L-carnitine than red meats. Since L-carnitine is the precursor of TMAO, they are much less likely to cause TMAO production.

Why Do Plant Proteins Decrease Your Risk Of Premature Death?

Whole Grains: Whole grains have been much maligned in recent years. They have been lumped in with sugar and refined grains and have been added to everyone’s “naughty list”.

  • If you are following a low-carb diet, you are told to avoid all grains.
  • If you are following a Paleo diet, you are told our paleo ancestors ate no grains.
  • If you are trying to avoid lectins…you get the point.

That’s unfortunate, because whole grains are very healthy. In a recent issue of “Health Tips From the Professor” I shared a study showing that whole grain consumption reduced the risk of premature death from heart disease, cancer, and all causes. The current study shows essentially the same thing.

The only question is why whole grains are uniquely effective at decreasing premature death from cardiovascular disease and all causes in this study. Why aren’t all plant proteins equally effective? I will share both a suggested mechanism and perspective.

Mechanism:

  • In a recent issue of “Health Tips From The Professor” I reported a study showing that grains and a few other foods contain a unique type of fiber called resistant starch that suppress growth of the gut bacteria which convert L-carnitine to TMAO. This may be why whole grains are uniquely effective at reducing the risk of cardiovascular disease and premature death.
  • Some refined grains are also good sources of resistant starch. However, I don’t recommend them because they lack the antioxidants, vitamins, phytonutrients, and insoluble fiber found in whole grains.

Perspective:  

The fact no other plant protein source significantly reduced heart disease risk in this study is most likely an artifact of the study.

  • The study asked what happens when you change 15 grams of the protein in your diet from red meat protein to different kinds of plant protein. That question was easy to answer for grains because they are a major source of protein in the American diet. However, Americans don’t get enough protein from other high protein plant foods like beans and legumes or nuts and seeds to provide a statistically valid answer to that question.
  • However, all plant foods have their own health benefits. They are excellent sources of antioxidants and phytonutrients that provide heart health benefits.
  • In addition, each plant food provides a different blend of fibers and supports different populations of gut bacteria with different health benefits. For example, fiber from fruits and vegetables is associated with a lower risk of cancer.

What Does This Study Mean For You?

dairy products and heart disease questionsA recent study has shown that changing as little as 20% of the protein in our diet from animal protein to plant protein significantly reduces our risk of premature death from cardiovascular disease, stroke, and from all causes.

The effect of replacing 2 ounces of red meat, 1 egg, or 2 servings of dairy with an equivalent amount of plant protein was equally beneficial.

Previous studies show that diet context is important. A small amounts of animal protein in the context of a whole food, primarily plant-based diet is much less likely to cause harm and may provide benefit. For example:

  • Eggs are high in cholesterol but are also excellent sources of low-fat protein and nutrients that may be missing in a plant-based diet.
    • Previous studies suggest that adding eggs to the typical American diet may increase risk of cardiovascular disease and premature death.
    • In contrast, adding eggs to a primarily plant-based diet, such as found in China and Japan, appears to decrease risk of cardiovascular disease and premature death.
  • Dairy foods are high in saturated fat but are excellent sources of calcium, vitamin D, and other nutrients that may be missing in a plant-based diet.
    • Eating dairy foods, even high-fat dairy foods, has relatively little effect on cardiovascular disease risk in the context of the typical high-fat, high-sugar American diet.
    • Eating dairy foods, even high-fat dairy foods, in the context of a healthy plant-based diet appears to lower cardiovascular disease risk.
  • Red meat has multiple suggested mechanisms for it increasing the risk of death from cardiovascular disease. However, diet context still matters.
    • If you are thinking in terms of a juicy 8-ounce steak with a baked potato and sour cream, red meat is probably not a healthy choice.
    • However, if you are thinking of 2-3 ounces of lean steak in a vegetable stir fry or a green salad, red meat may be a healthier choice.
    • Grass fed beef should not be considered a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • White meat does not appear to affect your risk of developing cardiovascular disease.
  • Whole grains significantly decreased the risk of premature death from cardiovascular disease and death from all causes. This may be because whole grains contain a unique type of fiber called resistant starch that suppresses the growth of the gut bacteria which convert L-carnitine to a heart-damaging compound called TMAO.
    • Notice that I specified “whole grain”. While some refined grains are also a good source of resistant starch, they lack the other heart healthy nutrients and phytonutrients found in whole grains.
      • Wonder Bread, Frosted Flakes, Honey Bunches of Oats, and white-flour pasta are not on my approved list. I agree with low-carb enthusiasts about eliminating them from our diets.
      • You should also be aware that “whole grain” on the label means nothing. You want to choose foods that say “100% whole grain”.
    • Finally, this study only focused on plant protein sources. It is important to remember that other plant foods are an excellent source of antioxidants, phytonutrients, and fiber. Each plant food provides unique heart health benefits.

The Bottom Line

A recent study has shown that changing as little as 20% of the protein in our diet from animal protein to plant protein significantly reduces our risk of premature death from cardiovascular disease, stroke, and from all causes.

The effect of replacing 2 ounces of red meat, 1 egg, or 2 servings of dairy with an equivalent amount of plant protein was equally beneficial. White meat did not affect the risk of cardiovascular disease or premature death.

  • Grass fed beef should not be considered a “get out of jail free card”. Grass fed beef is modestly lower in cholesterol and saturated fat. However, those are only two of six potential mechanisms for the link between red meat consumption and cardiovascular disease.
  • Diet context is important. Small amounts of animal protein in the context of a whole food, primarily plant-based diet appear to be much healthier for us than large amounts of animal protein in the context of the high-fat, high-sugar American diet.

On the flip side of the equation, whole grains significantly decreased the risk of premature death from cardiovascular disease and death from all causes. This has also been seen in other recent studies.

  • Notice that I specified “whole grain”. Wonder Bread, Frosted Flakes, Honey Bunches of Oats, and white-flour pasta are not on the list.
  • You should also be aware that “whole grain” on the label means nothing. You want to choose foods that say “100% whole grain”.
  • Finally, this study only focused on plant protein sources. It is important to remember that other plant foods are an excellent source of antioxidants, phytonutrients, and fiber. Each plant food provides unique heart health benefits.

For more details, read the article above, especially the “What Does This Study Mean For You?” section.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Should I Avoid Whole Grains?

Will Whole Grains Kill Me?

Whole GrainsIt seems like just yesterday that health experts all agreed that whole grains were good for us. After all:

  • They are a good source of fiber, B vitamins, vitamin E, and the minerals magnesium, iron, zinc, manganese, and selenium.
  • Their fiber fills you up, so you are less likely to overeat. This helps with weight control.
  • Their fiber also supports the growth of friendly bacteria in your gut.

In fact, the USDA still recommends that half of the grains we eat should be whole grains. And, outside experts, not influenced by the food industry, feel this recommendation is too low. They feel most of the grains we eat should be whole grains. Foods made from refined grains should be considered as only occasional treats.

Then the low-carb craze came along. Diets like Paleo and Keto were telling you to avoid all grains, even whole grains. Even worse, Dr. Strangelove and his colleagues were telling you whole grains contained something called lectins that were bad for you. Suddenly, whole grains went from being heroes to being villains.

You are probably asking, “Should I avoid whole grains?” What is the truth? Perhaps the best way to resolve this debate is to ask, how healthy are people who consume whole grains for many years? This week I share a recent study (G Zong et al, Circulation, 133: 2370-2380, 2016) that answers that very question.

How Was The Study Done?

This study was a meta-analysis of 14 clinical trials that:

  • Enrolled a total of 786,076 participants.
  • Obtained a detailed diet history at baseline.
  • Followed the participants for an average of 15 years (range = 6-28 years).
  • Determined the effect of whole grain consumption on the risk of death from heart disease, cancer, and all causes.

Will Whole Grains Kill Me?

deadDr. Strangelove and his colleagues are claiming that whole grains cause inflammation, which increases your risk of heart disease and cancer. Heart disease and cancer are the leading causes of death in this country. In fact, according to the CDC, heart disease and cancer accounted for 44% of all deaths in the US in 2017.

Therefore, if Dr. Strangelove and his colleagues were correct, consumption of whole grains should increase the risk of deaths due to heart disease and cancer – and increase the risk of death due to all causes.

That is not what this study showed.

When the highest whole grain intake (5 servings/day) was compared with the lowest whole grain intake (0 servings/day), whole grain consumption reduced the risk of death from:

  • Heart disease by 18%.
  • Cancer by 12%.
  • All causes by 16%.

Furthermore, the effect of whole grains on mortality showed an inverse dose response. Simply put, the more thumbs upwhole grains people consumed, the lower the risk of deaths from heart disease, cancer, and all causes.

However, the dose response was not linear. Simply going from 0 servings of whole grains to one serving of whole grains reduced the risk of death from.

  • Heart disease by 9%.
  • Cancer by 5%.
  • All causes by 7%.

The authors concluded: “Whole grain consumption was inversely associated with mortality in a dose-response manner, and the association with cardiovascular mortality was particularly strong and robust. These observations endorse current dietary guidelines that recommend increasing whole grain intake to replace refined grains to facilitate long-term health and to help prevent premature death.”

The authors went on to say: “Low-carbohydrate diets that ignore the health benefits of whole grain foods should be adopted with caution because they have been linked to higher cardiovascular risk and mortality.”

Should I Avoid Whole Grains?

Question MarkAs for the original question, “Should I avoid whole grains?”, the answer appears to be a clear, “No”.

The strengths of this study include the large number of participants (786,076) and the demonstration of a clear dose-response relationship between whole grain intake and reduced mortality.

This study is also consistent with several other studies that show whole grain consumption is associated with a lower risk of heart disease, diabetes, cancer – and appears to lead to a longer, healthier life.

In short, it appears that Dr. Strangelove and the low-carb enthusiasts are wrong. Whole grains aren’t something to avoid. They reduce the risk of heart disease, diabetes, and cancer. And they reduce the risk of premature death. We should be eating more whole grains, not less.

However, the authors did point out that this study has some weaknesses:

  • It is an association study, which does not prove cause and effect.
  • Study participants who consumed more whole grains also tended to consume more fruits and vegetables – and less red meat, sodas, and highly processed foods.

However, I would argue the second point is a strength, not a weakness. We need to give up the idea that certain foods or food groups are “heroes” or “villains”. We know that primarily plant-based diets like the Mediterranean and DASH diets are incredibly healthy. Does it really matter how much of those health benefits come from whole grains and how much comes from fruits and vegetables?

The Bottom Line

Dr. Strangelove and low-carb enthusiasts have been telling us we should avoid all grains, including whole grains. Is that good advice?

If Dr. Strangelove and his colleagues were correct, consumption of whole grains should increase the risk of deaths due to the top two killer diseases, heart disease and cancer. Furthermore, because heart disease and cancer account for 44% of all deaths in this country, whole grain consumption should also increase the risk of death due to all causes.

A recent study showed the exact opposite. The study showed:

When the highest whole grain intake (5 servings/day) was compared with the lowest whole grain intake (0 servings/day), whole grain consumption reduced the risk of death from:

  • Heart disease by 18%.
  • Cancer by 12%.
  • All causes by 16%.

Furthermore, the effect of whole grains on mortality showed an inverse dose response. Simply put, the more whole grains people consumed, the lower the risk of deaths from heart disease, cancer, and all causes.

However, the dose response was not linear. Simply going from 0 servings of whole grains to one serving of whole grains reduced the risk of death from.

  • Heart disease by 9%.
  • Cancer by 5%.
  • All causes by 7%.

The authors concluded: “Whole grain consumption was inversely associated with mortality in a dose-response manner, and the association with cardiovascular mortality was particularly strong and robust. These observations endorse current dietary guidelines that recommend increasing whole grain intake to replace refined grains to facilitate long-term health and to help prevent premature death.”

The authors went on to say: “Low-carbohydrate diets that ignore the health benefits of whole grain foods should be adopted with caution because they have been linked to higher cardiovascular risk and mortality.”

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Health Tips From The Professor