processed meat

Does Meat Consumption Increase Disease Risk?

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Is It Meat Or Something Else?

Author: Dr. Stephen Chaney 

ArgumentWe are told we should be consuming more protein. But where should we get our protein?

Meat is an obvious choice. But meat consumption is controversial. The arguments are intense.

There are those who claim that meat consumption, particularly red meat, increases our risk of cancer, heart disease, diabetes, and many other diseases. Others claim that meat has been maligned. It doesn’t increase disease risk. We should eat more of it, not less.

The problem is that both sides are basing their claims on published clinical studies. Studies on meat consumption and disease risk are all over the map.

I have covered this controversy in previous issues of “Health Tips From the Professor”. In attempting to make sense of the conflicting data I made the observation that studies showing meat consumption reduced disease risk tended to come from third world countries while studies showing meat consumption increased disease risk tended to come from high-income western countries.

So, my interest was peaked when I saw a very large study (K Papier et al, BMC Medicine,: 19:53, 2021) on meat consumption and disease risk in the UK.

How Was This Study Done?

clinical studyThe investigators used data from the UK Biobank Study, a study that recruited 503,317 young men and women throughout the UK between 2006 and 2010. Upon entry into the study participants completed questionnaires about physical data (height, weight, etc), biological data (blood sugar, cholesterol levels, etc.), and diet.

This particular study used data from a subset (474,985) participants who completed a 24-hour dietary recall questionnaire.

Participants were then linked to the National Health Service database to assess the first occurrence of the 25 leading non-cancerous causes of hospital admissions for each patient and followed for an average of 8 years.

Cancer admissions were excluded from this study because the International Agency for Research on Cancer (IARC), the cancer agency of the WHO, has already classified red meat as a probable carcinogen and processed meat as a likely carcinogen.

Does Meat Consumption Increase Disease Risk?

SteakThe investigators looked at four distinct categories of meat consumption (total meat, red meat, processed meat, and poultry) and the risk of 25 common diseases (excluding cancer). In each case, they divided meat consumption into quartiles and compared the disease risk for those in the highest quartile to those in the lowest quartile.

For the sake of simplicity, I will only report the most significant disease risks (those with p ≤001).

Total Meat Consumption (Lowest quartile = 1.2 oz/d; Highest quartile = 4.1 oz/d):

Disease Increased

Risk
Heart Disease 29%
Stroke 24%
Diverticular Disease 29%
Colon Polyps 14%
Diabetes 85%

Red Meat Consumption (Lowest quartile = 0.2 oz/d; Highest quartile = 2.0 oz/d):

Disease Increased

Risk
Heart Disease 25%
Stroke NS
Diverticular Disease 26%
Colon Polyps 11%
Diabetes 53%

Processed Meat Consumption (Lowest quartile = 0.15 oz/d; Highest quartile = 1.0 oz/d):

Disease Increased

Risk
Heart Disease 17%
Stroke 23%
Diverticular Disease 18%
Colon Polyps 11%
Diabetes 52%

Poultry Consumption (Lowest quartile = 1.2 oz/d; Highest quartile = 4.1 oz/d):

Disease Increased

Risk
Heart Disease 12%
Stroke NS
Diverticular Disease 18%
Colon Polyps 11%
Diabetes 32%
GERD 16%
Gastritis 10%

My evaluation of the data is:

  • These differences are highly significant (p <001) and the study size was very large (~475,000 participants), so the increased risk is probably true for a high-income Western country like the UK.
    • However, some of these differences are relatively small. It’s easy to understand how they might be missed in smaller studies.
    • Even increased risk in the 25-30% range might disappear in studies that combine data from high-income countries and third world countries.
    • With this perspective it is easy to understand why previous studies have been so confusing.
  • Because the investigators looked at the effect of each kind of meat separately, one can get a better idea of the relative contribution of each meat to various diseases [With, of course, the caveat that people who consume more red meat also tend to consume more processed meat and vice versa.] For example:
    • Red meat appears to contribute more to heart disease risk than processed meat or poultry – possibly due to its high saturated fat and cholesterol content.
    • Processed meat appears to contribute more to stroke risk than red meat or poultry – possibly due to added nitrates and other food additives.
    • All meats appear to contribute to diverticular disease – possibly due to a change in gut bacteria because meats replace plant foods in the diet.
  • The increased risk of GERD and gastritis associated with poultry consumption was surprising, but the increased risk was small.

The authors concluded, “Our findings from this large prospective study of British adults show that meat consumption is associated with higher risks of several common conditions but a lower risk of iron deficiency anemia…Additional research is needed to evaluate whether these differences in risk reflect causal relationships, and if so what proportion [of these outcomes] could be prevented by decreasing meat consumption.”

Is It Meat Or Something Else?

Question MarkOf course, the question, “Is it meat or something else in our diet that is causing the increased risk of disease?” One hint that something else might be contributing to disease risk came when the authors corrected the data for obesity. The results are shown below:

Total Meat Consumption Corrected For Obesity

Disease Increased

Risk

 Corrected

For Obesity
Heart Disease 29% 17%
Stroke 24% 22%
Diverticular Disease 29% 18%
Colon Polyps 14% 10%
Diabetes 85% 33%

Red Meat Consumption Corrected For Obesity

Disease Increased

Risk

 Corrected

For Obesity
Heart Disease 25% 16%
Stroke NS NS
Diverticular Disease 26% 17%
Colon Polyps 11% 8%
Diabetes 53% 21%

Processed Meat Consumption Corrected For Obesity

Disease Increased

Risk

 Corrected

For Obesity
Heart Disease 17% 9%
Stroke 23% 17%
Diverticular Disease 18% 17%
Colon Polyps 11% 8%
Diabetes 52% 24%

Poultry Consumption Corrected For Obesity

Disease Increased

Risk

 Corrected

For Obesity
Heart Disease 12% 8%
Stroke NS NS
Diverticular Disease 14% 10%
Colon Polyps 6% 7%
Diabetes 32% 14%
GERD 16% 17%
Gastritis 10% 12%

When corrected for obesity, the risk of:

  • Heart disease decreased by 33-47%.
  • Diverticular disease decreased by 23-38%.
  • Diabetes decreased by 54-61%.

But how do we interpret that? It would be easy to conclude that the influence of meat consumption on heart disease, diverticular disease, and diabetes is small. However, that’s not the real world. People aren’t meat eaters or overweight. In the real world, people are often meat eaters and overweight.

So, the important question to ask is why so many meat eaters are overweight.

  • It could simply be a question of calories. A serving of steak is around 680 calories, while a serving of beans is around 110 calories.
  • It could be what is eaten with the steak or beans. A medium baked potato with butter and sour cream adds 300-500 calories. A vegetable stir fry adds 170 calories.
  • It could be how we cook it. In our country over 50% of chicken we eat is fried. And to make matters worse, we often add French Fries and other highly processed foods to our fried chicken meal.

What Does This Study Mean For You?

confusionThis study shows that in a high-income western society like ours, meat consumption is likely to increase our risk of several diseases, For example:

  • Red meat is associated with increased risk of heart disease, diabetes, and diverticular disease.
  • Processed meat is associated with increased risk of stroke, diabetes, and diverticular disease.
  • Poultry consumption is associated with increased risk of diabetes and digestive diseases.
  • All three kinds of meat are associated with obesity.

While it is easy to blame meat consumption for all our ills, it may be how we cook it and what we eat along with it.

Perhaps we should eat our meat the way they do in Third World countries. Rather than eating it as a main course, perhaps we should use it as flavoring for a vegetable stir fry or a lentil stew.

The Bottom Line

A recent study looked at the association of meat consumption with disease risk in the UK. It found that:

  • Red meat is associated with increased risk of heart disease, diabetes, and diverticular disease.
  • Processed meat is associated with increased risk of stroke, diabetes, and diverticular disease.
  • Poultry consumption is associated with increased risk of diabetes and digestive diseases.
  • All three kinds of meat are associated with obesity.

For more information 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.

____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading Biochemistry textbooks for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 54 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Will Processed Meat Kill You?

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What Is The Truth About Meat?

Author: Dr. Stephen Chaney 

Vegans will tell you that any meat is bad for you. Keto enthusiasts haven’t found a meat they don’t like. To them grains and most fruits and vegetables are the problem.

But what about those of us who aren’t at either extreme? Which meat, if any, should be part of a healthy diet? And how much of them should we eat?

For years the paradigm had been clear:

  • Fish was best, especially fish rich in omega-3s. They were good for your heart and your brain. And some studies suggested that high intake of omega-3-rich fish might help you live longer.
  • Poultry and other white meats were neutral.
  • Red meat was probably bad for you. It was high in saturated fat and cholesterol, and some studies linked it to an increased risk of heart disease. Plus, the International Agency for Research on Cancer (IARC), an agency of the WHO, listed it as a probable carcinogen. [Note: Recent studies have questioned concerns about red meat. I will discuss this below.]
  • Processed meats were considered a “no-no” The IARC listed processed meat as a definite carcinogen for humans based on studies linking it to colon, stomach, lung, and pancreatic cancers. It is also linked to an increased risk of heart disease.

However, most of these studies were done in the United States. And our diet is very different from that of many other countries.

That’s why a recent study (R Iqbal et al, American Journal of Clinical Nutrition, 114:1049-1058, 2021) caught my eye. The study was designed to measure the association between unprocessed red meat & poultry and processed meat intake with the risk both mortality and major cardiovascular disease with cancer as a secondary end point. And the study used data from 21 countries around the world except the United States.

How Was This Study Done?

Clinical StudyThe authors used data from the Prospective Urban Rural Epidemiology (PURE) study. The study is a large-scale (164,007 individuals), prospective (meaning it follows the individuals over time rather than taking measurements from them at a single time) study. The individuals in the study were aged 35-70 years and were followed for an average of 9.5 years.

The individuals came from 21 low-, middle-, and high-income countries.

  • The low-income countries included Bangladesh, India, Pakistan, Tanzania, and Zimbabwe.
  • The middle-income countries included Argentina, Brazil, Chile, China, Columbia, Iran, Poland, South Africa, and Turkey.
  • The high-income countries included Canada, Saudi Arabia, Sweden, and the United Arab Emirates. [Note: The United States was not included in the study.]

At the beginning of the study and at 3, 6, and 9 years the following data were collected from everyone enrolled in the study.

  • Demographic information (age, sex, location, education, wealth index, and smoking status).
  • Lifestyle information (diet and physical activity).
  • Health history.
  • Medication use.
  • Cardiovascular events and mortality.

Will Processed Meat Kill You?

The authors compared high intake of processed meats (5 ounces per week, the equivalent of two sausages/week) with zero intake of processed meats. They reported that high intake of processed meats increased the risk of:

  • Mortality by 51%.
  • Major cardiovascular disease by 46%.
  • Non-cardiovascular mortality by 50%
  • Cancer by 84%.
  • Heart attack by 62%.
  • Stroke by 56%.

Furthermore, even as little as 1.5 ounces of processed meat per week significantly increased the risk of mortality.

For red meat and poultry, the authors compared high intake (9 ounces per week) with low intake (2 ounces per week). For both red meat and poultry they did not find any association between high weekly intake and any of the health outcomes.

[I would note however, that many Americans consume 4 ounces of chicken or an 8-ounce steak at dinner – that’s one meal on one day. The corresponding weekly intake would be 28 ounces of chicken or 56 ounces of red meat. That’s significantly higher than the highest weekly intake used in this study.]

The authors concluded, “We observed no significant association between the consumption of unprocessed red meat and poultry intake and health outcomes. And higher intake of processed meat was associated with higher risks of mortality and cardiovascular disease. These findings may indicate that limiting the intake of processed meat should be encouraged.”

In my opinion, there are so many studies linking the consumption of processed meat with heart disease, cancer, and premature death that the last sentence of their conclusion should have said, “These findings unambiguously confirm that limiting the intake of processed meats should be encouraged.”

What Is The Truth About Meat? 

truthRed Meat:

Yes, there is a lot of confusion about red meat. Many studies, like this one, find no adverse health effects associated with red meat consumption. That has led many experts to conclude that the dangers of red meat have been greatly exaggerated.

I think we should dig a little deeper. Most of the studies showing that red meat consumption increases the risk of heart disease, cancer, and mortality have been done in this country. So, perhaps we should be asking what is different about red meat consumption in our country.

There are several factors to consider:

  • Cooking Methods: The authors of this article pointed out that we often grill our meat at high temperatures which causes the formation of cancer-causing chemicals, while many of the countries in the PURE database stew their red meat at much lower temperatures.
  • Diet Context: As I have explained in a previous article of Health Tips From the Professor, fruits, vegetables, and whole grains are the antidotes to the cancer-causing chemicals formed when we cook red meat. And they bind to cholesterol in the intestine and flush it out of the body. Finally, they dilute the saturated fat in red meat with polyunsaturated fats, which helps create a healthier balance of fats.

In this country we often pair our steaks with French fries or a baked potato loaded with butter and sour cream. However, in low- and middle-income countries red meat is an expensive luxury and is often used as a garnish to dishes containing lots of vegetables and whole grains.

  • Amount Consumed: As a mentioned above, the amount of red meat most Americans consume in a week far exceeds the highest weekly intake of red meat in this study. The highest weekly consumption of red meat in this study is more consistent with using red meat as a garnish than as a main course.

Poultry:

For poultry, there is no confusion. Studies done in this country also find no association between poultry consumption and cardiovascular disease, cancer, or mortality. That may be due to a healthier fat profile and the ways in which poultry is usually cooked.

Processed Meat:

For processed meat, there is also no confusion. Virtually every published study from across the world agrees that it increases the risk of cancer, heart disease, and premature death. And the effect is not trivial. This study suggests that just 2 sausages a week is enough to increase your risk of premature death by 50%! So, the answer to the question, “Will processed meat kill you?” appears to be, “Yes”.

The authors of this article pointed out that the saturated fat and cholesterol in processed meat and red meat were very similar. They didn’t mention it, but the cooking techniques are also similar. So, neither of these explain why processed meat is so bad for us.

However, the amounts of preservatives and food additives in processed and unprocessed meats differ greatly. Based on this, the authors of the study and many other experts postulate that it is the preservatives and food additives that are responsible for the health risks of processed meats.

What Does this Mean For You? 

This study agrees with many other studies showing that processed meats are bad for us. The authors recommend limiting your intake of processed meats.

However, their data show that as little as two strips of bacon, one hot dog, or half a large sausage per week significantly increases your risk of heart disease, cancer, and premature death. Based on that, my advice would be to avoid processed meats as much as possible.

As I described above, most experts feel that it is the preservatives and food additives that are responsible for the health risks associated with processed meats.

Some studies suggest that nitrates in processed meats may be the main culprit. Based on that belief, some food companies are offering nitrate-free processed meats as a healthier option.

However, there still may be some additives in nitrate-free processed meats (read the label carefully), and we have no clinical studies showing that the nitrate-free processed meats in the marketplace are good for us.

Red meat is more confusing. This study and others suggest it poses no health hazards. And many experts are telling you that the warnings about consuming red meat were overblown. They are telling you that red meat is good for you.

However, some studies suggest that red meat increases your risk of heart disease, cancer and premature death. When you examine the data behind the studies, I think that better advice would be that red meat can be good for you or bad for you depending on three factors:

  • Portion size: We should think of red meat as a garnish rather than a main course – 3-4 ounces is a healthy portion size. 8-12 ounces may be too much.
  • Cooking method: Many of the bad things associated with red meat are the result of high temperature cooking, especially over a flame or on a grill. Choose low temperature cooking methods whenever possible.
  • Diet context: Whole fruits, vegetables and whole grains are the antidotes to all the bad things associated with red meat. 3-4 ounces of red meat in a vegetable stir fry or green salad is likely to be much better for you than an 8-ounce steak with French fries.

Also, red meat already has more than enough saturated fat and cholesterol. Adding foods or sauces high in fat and cholesterol may overload the body’s ability to safely process them. But adding vegetables or vegetable oils helps to restore a better balance between good and bad fats.

Finally, this and other studies agree that white meat is healthy. My only advice is:

  • Avoid white meat that has been fried (especially by fast food restaurants that only change their oil every 20,000 miles) or cooked with fatty sauces.
  • Think of the whole diet rather than just the protein source. White meat will be the healthiest as part of a whole food, primarily plant-based diet.

The Bottom Line 

A recent study reported that eating as 5 ounces of processed foods per week increases your risk of heart disease, cancer, and premature death by 50%. That is equivalent to two sausages per week!) The authors of the study recommended that you limit your intake of processed meats.

However, the study showed that even as little as 1.5 ounces (2 strips of bacon, one hot dog, or half of a large sausage) per week significantly increases your risk of all three. Based on that data, my recommendation is to consider avoiding processed meat altogether.

The study reported that unprocessed red and white meat are not associated with increased health risks. I put those findings into the context of other published studies on the topic. I discuss my recommendations for unprocessed red and white meat in the article above.

For more information 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.

____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_____________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 54 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Can You Cut Your Risk Of Heart Disease By 90%?

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The Effect Of Ultra-Processed Foods On Heart Disease Risk
 

Author: Dr. Stephen Chaney

strong heartHeart disease is a killer. It continues to be the leading cause of death – both worldwide and in industrialized countries like the United States and the European Union. When we look at heart disease trends, it is a good news – bad news situation.

  • The good news is that heart disease deaths are continuing to decline in adults over 70.
    • The decline among senior citizens is attributed to improved treatment of heart disease and more seniors following heart-healthy diets.
  • The bad news is that heart disease deaths are starting to increase in younger adults, something I reported in an earlier issue of “Health Tips From the Professor.”
    • The reason for the rise in heart disease deaths in young people is less clear. However, the obesity epidemic, junk and convenience foods, and the popularity of fad diets all likely play a role.

Everyone has a magic diet to reduce the risk of heart disease. The American Heart Association tells us to avoid fats, especially saturated fats. Vegans tell us to avoid animal protein. Paleo and Keto enthusiasts tell us carbs are the problem.

But what if we eliminated junk and convenience food AND switched to a really healthy diet? How much would that reduce heart disease risk? A recent study (Y Willett et al, The American Journal of Medicine, in press, 2026) looked at the first part of that question. It looked at the effect of ultra-processed food (what we call junk and convenience foods) consumption on the risk of developing heart disease.

How Was This Study Done?

Clinical StudyThe scientists analyzed data from 4787 participants in the most recently published (2021 to 2023) National Health and Nutrition Examination Survey (NHANES). The average age of participants in the survey was 55 years, with 56% of them being women.

All the participants in this study had completed a dietary survey of everything they ate over the last two days. They also reported whether they had ever experienced a heart attack or stroke.

Ultra-processed foods were defined as foods that are industrially modified and loaded with added fats, sugars, starches, salts, and chemical additives.

The percentage of ultra-processed foods in their diet was calculated, and the participants were divided into quartiles based on the percentage of ultra-processed foods they consumed.

Participants with the highest quartile of ultra-processed food consumption were compared to those in the lowest quartile with respect to the risk of cardiovascular disease (self-reported heart attack or stroke). The data were corrected for age, sex, race, ethnicity, smoking status, and income.

The Effect Of Ultra-Processed Foods On Heart Disease Risk

Fast Food DangersThe results were striking:

  • The participants in the highest quartile for ultra-processed food consumption had a 47% higher risk of heart disease compared to those in the lowest quartile for ultra-processed food consumption.

The authors concluded, “Adults who consumed the highest amount of ultra-processed foods had a statistically significant 47% increased risk of heart disease. Large scale randomized trials are needed, but in the meantime, health care providers should advise patients to decrease consumption of ultra-processed foods in addition to adopting other therapeutic lifestyle changes and adjunctive drug therapies of proven benefit.”

The authors recognized the difficulty of making those changes in a world where ultra-processed foods are ubiquitous and cheap.

However, they drew parallels to tobacco use in this country. They said, “Just as it took decades for the dangers of smoking to become widely accepted, reducing reliance on ultra-processed foods may take time. This is partly due to the influence of large multinational companies that dominate the food market. In addition, many people face limited access to healthier food options.”

They went on to say, “Addressing ultra-processed foods isn’t just about individual choices – it’s about creating environments where the healthy option is the easy option.”

Can You Cut Your Risk Of Heart Disease By 90%?

The short answer is, “probably not”. But you can reduce the risk of heart disease by a lot – and probably by a lot more than 47%.

That’s because this study did not look at what the participants were replacing the ultra-processed foods with. Some participants may have replaced them with whole food, primarily plant-based diets. Others may have replaced ultra-processed foods with whole food, meat-based diets high in saturated fats.

So, let’s look at the other side of the equation – how much you can reduce your risk of heart disease by eating a healthier diet. In a recent issue of “Health Tips From The Professor”, I reviewed a meta-analysis published in 2022 that looked at 99 clinical studies with tens of thousands of participants that measured the associations between foods or food groups and heart disease risk.

That study reported that:

  • Processed Meat: A single serving of processed meat increased heart disease risk by 27% to 44%.
  • Red Meat: Unprocessed red meat increased heart disease risk by as much as 27% – but only at ≥3 servings per day. The results with lower intakes were inconsistent – some studies showed increased risk, but others did not.
  • Poultry, Eggs, and Dairy Foods: They did not appear to affect heart disease risk.
  • Fish: Two to four servings per week of fatty fish decreased heart disease risk by around 12%.
  • Fruit: Two servings per day of fruit reduced heart disease risk by 21-32%.Vegan Foods
  • Vegetables: Two servings of vegetables per day reduced heart disease risk by 18-21%.
  • Legumes (beans and peas): Four servings per week reduced the risk of heart disease by around 14%.
  • Nuts: One serving (a handful) per day reduced the risk of heart disease by around 25%. 
  • Whole Grains: Two servings of whole grains per day reduced the risk of heart disease by 25%-34%.
  • Overall: When heart-healthy foods were consumed as part of the Mediterranean diet heart disease risk was reduced by 47%. Similar overall reductions in heart disease risk are likely with other heart-healthy diets like DASH, MIND, Flexitarian (flexible semi-vegetarian), and vegan diets.

In summary:

  • The first study shows that eliminating ultra-processed foods (junk and convenience foods) from your diet can decrease heart disease risk by 47% – but doesn’t tell us what the ultra-processed foods were replaced with. And it would take a much larger study to determine which food swaps were most effective at reducing heart disease risk.
  • The second study was a meta-analysis that told us that eating more fish and plant foods in the context of a heart-healthy diet can decrease your risk of heart disease by 47% – but doesn’t tell us what those healthy foods were replacing. And many of the individual studies included in the meta-analysis were conducted when ultra-processed food consumption was much less than it is today.

It would be tempting to add 47% plus 47% and conclude that eliminating ultra-processed food consumption and replacing ultra-processed foods with heart-healthy foods could decrease your risk of heart disease by 94%. But it’s not that simple. There are too many unanswered questions from these studies.

But it is safe to say that if we eliminated ultra-processed foods AND replaced them with heart-healthy foods in the context of a heart-healthy diet, we should be able to reduce our heart disease risk by more than 47% – perhaps much more.

What Do These Studies Mean For You?

There are two important lessons from these studies:

#1: Eliminating ultra-processed foods from your diet will significantly decrease your risk of heart disease.

And it isn’t just heart disease. Other recent studies have shown that eliminating ultra-processed foods from your diet helps you:

  • Control your weight (It is perhaps the most important lifestyle change to make if you want to maintain GLP-1-aided weight loss).
  • Reduce your risk of cancer.
  • Reduce your risk of diabetes.
  • Reduce your risk of inflammatory diseases.
  • Reduce anxiety and depression.
  • Increase your healthspan (your healthy years).

In short, ultra-processed foods are killers.

#2: Replacing ultra-processed foods with heart-healthy foods (fruits, vegetables, legumes, nuts, whole grains, and fish) in the context of a healthy diet (Mediterranean, DASH, MIND, Flexitarian, and vegan, for example) is likely to decrease your risk of heart disease even more.

  • And if your diet consists of mostly heart-healthy foods, you can add moderate amounts of heart-neutral foods (poultry, eggs, and dairy).
  • And the latest evidence suggests that you can even add small amounts of red meat in the context of a heart-healthy diet (As I have said in previous issues of “Health Tips From the Professor”, plant foods contain the antidotes to all the bad things about red meat.)

Finally, you might ask why I emphasize both heart-healthy foods and heart-healthy diets. There are two reasons:

  • Most of us think in terms of foods rather than diets.
  • The food industry is only too happy to provide us with ultra-processed foods for “heart-healthy” diets like the vegan and Mediterranean diet.

The Bottom Line

Two recent studies have shown how each of us can dramatically reduce our risk of heart disease.

  • The first study showed that eliminating ultra-processed foods from our diet can significantly decrease our heart disease risk – but didn’t tell us what the ultra-processed foods were replaced with.
  • The second study showed that eating more heart-healthy foods in the context of a heart-healthy diet can significantly decrease our risk of heart disease – but didn’t tell us what those healthy foods were replacing.

Taken together, those studies show us a clear path for dramatically decreasing our heart disease risk.

For more details about these studies and what they mean 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.

 _____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

 

Does Meat Increase Diabetes Risk?

by

Why Does Meat Increase Diabetes Risk?

Author: Dr. Stephen Chaney

diabetesThe statistics for type 2 diabetes are alarming. In the United States:

  • 38.1 million adults (15% of the adult population) had diabetes in 2021, with 95% of them having type 2 diabetes.
    • 8.7 million of those adults were unaware they had diabetes.
    • If current trends continue, by 2030 the number of adults with diabetes is projected to increase by 54% to around 55 million.
  • Another 96 million Americans (33% of the population) have pre-diabetes. Unless they change their diet and lifestyle, most of them are destined to progress to type 2 diabetes in the next few years.
  • Diabetes is the eight leading cause of death in this country.
  • The costs associated with diabetes in the United States are currently around $410 billion and are projected to increase to around $622 billion by 2030.

The statistics are not much different worldwide:

  • Type 2 diabetes currently affects more than 500 million people worldwide and is expected to double by 2050.
  • Diabetes is also the 8th leading cause of death worldwide.

This is a major concern because diabetes dramatically increases the risk of:

  • Heart disease and stroke.
  • Certain types of cancer.
  • Painful neuropathies.
  • Vision loss and blindness.
  • Cognitive decline and Alzheimer’s disease.

Just to name a few. Diabetes affects your quality of life, and it can shorten your lifespan by several years.

So, you are probably wondering what you can do to decrease your risk of developing type 2 diabetes. There are lots of fad diets (low carb, low fat, low glycemic, high fiber, Paleo, Keto, etc.), but the weight of evidence is that your best bet for decreasing the risk of developing diabetes is a healthy diet that:

  • Is primarily plant-based.
  • Consists mostly of unprocessed or minimally processed foods.
  • Emphasizes healthy fats such as monounsaturated and omega-3 fats.
  • Includes lots of fruits and vegetables.
  • Emphasizes whole rather than refined grains.
  • Includes plant protein sources like beans, nuts, and seeds.
  • Has a low caloric density (which it will if you follow the guidelines above), so you can lose weight slowly and naturally.

But what about meat? Here the data are less clear. Several studies have suggested that eating red and processed meat increases your risk of type-2 diabetes. Studies on poultry are mixed with some studies suggesting they increase the risk of developing type 2 diabetes, and other studies suggesting they have no effect.

Unfortunately, the data from the previous studies were inconsistent, in part because the methods used to collect and analyze the data varied widely from study to study. In addition, the studies were primarily performed in the United States and Europe, so it was unclear whether the correlation between meat consumption and type 2 diabetes was universal, or whether it was restricted to western countries.

With this in mind, the authors of the current study (C Li et al, The Lancet Diabetes and Endocrinology, 12: 619-630, 2024) decided to perform a much more comprehensive study by combining studies from all across the world that used similar methodologies.

How Was This Study Done? 

clinical studyThis study was a meta-analysis of data obtained from the InterConnect project. The InterConnect project is registry of more than 200 studies from around the world. The investigators chose 31 studies with a total of 1,966,444 individuals from 20 countries for this meta-analysis based on the following criteria:

  • Participants in the studies were adults between 40 and 60 years old.
  • Participants were excluded from the study if they already had type 2 diabetes.
  • The diets of participants in the studies were assessed by having the participants fill out standardized dietary assessment forms at the beginning of the study.
  • Participants were followed for an average of 10 years (7-15 years) to see how many developed a newly diagnosed case of type 2 diabetes. During this time 10,271 participants in these studies developed type 2 diabetes.
  • The correlation between 3 types of meat (processed meat, red meat, and poultry) and type 2 diabetes was adjusted for other factors that affect the risk of diabetes (e.g., age, sex, ethnicity, smoking, drinking, physical activity, obesity, and family history of type 2 diabetes)

Does Meat Increase Diabetes Risk? 

High Blood SugarThe results of this meta-analysis were:

  • There was a log-linear (greater than linear) dose-response correlation without any obvious threshold or ceiling effect with the risk of developing type-2 diabetes for all three meats tested in this study.
  • For processed meat each 50-gram increase (equivalent to 4 slices of smoked ham) increases the risk of developing type 2 diabetes by 15%.
  • For unprocessed red meat each 100-gram increase (equivalent to 3.5 ounces of steak) increases the risk of developing type 2 diabetes by 10%.
  • For poultry each 100-gram increase (equivalent to 3.5 ounces of chicken) increases the risk of developing type 2 diabetes by 8%. However, after correcting for other diet and lifestyle factors that increase the risk of type 2 diabetes, the effect of poultry on diabetes risk was non-significant.

When they looked at the effect of replacing one type of meat with another:

  • Replacing 50 grams of processed meat with 100 grams of unprocessed red meat decreased the risk of diabetes by 7%.
  • Replacing 50 grams of processed meat with 100 grams of poultry decreased the risk of diabetes by 10%.
  • I should note that previous studies have shown that replacing either processed meat or unprocessed red meat with vegetable protein foods (beans, nuts, and seeds) significantly decreases the risk of developing diabetes.

 

When they looked at different regions of the world:

  • The effect of both processed and unprocessed red meat on type 2 diabetes risk was seen in America, Europe, Western Pacific regions, and east Asia.
  • However, no effect of either unprocessed or processed red meat on type 2 diabetes risk was seen in the Eastern Mediterranean and South Asia.

The authors concluded, “The consumption of meat, particularly processed and unprocessed red meat, is a risk factor for developing type 2 diabetes across populations. These findings highlight the importance of reducing meat consumption for public health and should inform dietary guidelines.”

Why Does Meat Increase Diabetes Risk?

Question MarkThis study supports and strengthens previous studies suggesting that we should add red and processed meats to the list of risk factors for developing type 2 diabetes. However, unless you are a vegan, the idea of giving up all red and processed meat is probably a non-starter.

Instead, let’s ask why red and processed meats increase diabetes risk. Is it the meat itself, or something else that triggers the increase in the risk of developing type 2 diabetes. Is it:

#1: Guilt By Association: Diets high in meats are also high in saturated fats, which increase the risk of diabetes.

#2: Guilt By Omission: Diets high in meats are often low in fruits, vegetables, nuts, and seeds – all healthy foods that lower diabetes risk.

#3: Guilt By Addition: Processed meats contain additives that can increase the risk of developing diabetes. For example, nitrates or nitrites are often added as preservatives. But they can be converted in the gut to N-nitroso compounds which increase inflammation, which in turn increases the risk of developing diabetes.

#4: Guilt By Cooking: High temperature grilling and frying creates compounds that create oxidative stress, which can increase the risk of developing diabetes.

#5: Guilt By Microbiome: The microbiome (gut bacteria) of heavy meat eaters is very different from the microbiome of people who eat a more plant-based diet. If a meat eater consumes a steak, their gut bacteria convert L-carnitine in the meat to a toxic compound called trimethylamine N-oxide (TMAO). However, if you were able to convince a vegan to eat the same steak, that wouldn’t happen.

#6: Guilt By Diet Context: The fact that there was no association between red and processed meat and diabetes in Mediterranean and South Asian regions gives us an important clue. The bad effects of red and processed meats are influenced by the context of the overall diet. What do the cuisines of the Mediterranean and South Asian regions have in common? They are both primarily whole food, plant-based cuisines.

I have discussed each of these mechanisms in more detail in an article in a recent edition of “Health Tips From the Professor”.

I also discussed ways to reduce the risk of each of these mechanisms, but if you don’t want to read the article,here is a spoiler alert:

  • Plant foods are the antidotes for the bad things associated with red and processed meats.
  • We should think of meat as a garnish for a primarily plant-based meal rather than a main course with a baked potato or fries as a garnish.

The Bottom Line

A recent study looked at the effects various meats on the risk of developing type 2 diabetes worldwide. The study found:

  • For processed meat each 50-gram increase (equivalent to 4 slices of smoked ham) increases the risk of developing type 2 diabetes by 15%.
  • For unprocessed red meat each 100-gram increase (equivalent to 3.5 ounces of steak) increases the risk of developing type 2 diabetes by 10%.
  • The effect of poultry on diabetes risk was non-significant.

When they looked at the effect of replacing one type of meat with another:

  • Replacing 50 grams of processed meat with 100 grams of unprocessed red meat decreased the risk of diabetes by 7%.
  • Replacing 50 grams of processed meat with 100 grams of poultry decreased the risk of diabetes by 10%.
  • I should note that previous studies have shown that replacing either processed meat or unprocessed red meat with vegetable protein foods (beans, nuts, and seeds) significantly decreases the risk of developing diabetes.

The authors concluded, “The consumption of meat, particularly processed and unprocessed red meat, is a risk factor for developing type 2 diabetes across populations. These findings highlight the importance of reducing meat consumption for public health and should inform dietary guidelines.”

For more details on this study, why meats increase diabetes risk, and 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.

 _____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 ________________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

 

Give Your Heart A Valentine

by

How Can You Give Your Heart A Valentine?

Author: Dr. Stephen Chaney

Happy valentines day

Valentine’s Day is just around the corner. You have probably already selected Valentine Day cards and gifts for those nearest and dearest to you. But what about your heart. It’s your most trusted companion. Doesn’t it deserve a valentine?

The best Valentine’s gift you could give your heart would be a heart healthy diet. But what is a heart-healthy diet?

You may remember the nursery rhyme, “Jack Sprat could eat no fat. His wife could eat no lean…” You may know people who fit these extremes. And in terms of diets these extremes might represent the vegan and keto diets in today’s world.

The nursery rhyme assures us that, “…between them they licked the platter clean.” But were their diets equally heart-healthy? Which of them would have been more likely to live a long and healthy life, free of heart disease?

If you search Mr. Google – even with AI assist – you might be confused. That’s because AI bases its recommendations on the quantity of posts, not the accuracy of posts. And lots of media influencers recommend both diets, and just about every popular diet in between for heart health.

But what does good science say on the topic of heart healthy diets? Fortunately, a recent comprehensive review and meta-analysis (G. Riccardi et al, Cardiovascular Research, 118: 1118-1204, 2022) has answered that question.

How Was The Study Done?

clinical studyThe investigators reviewed 99 clinical studies with tens of thousands of participants that looked at the associations between foods or food groups and heart disease risk.

Most of the studies were “prospective cohort” studies in which:

  • Populations are divided into groups (cohorts) based on the foods they consume…
  • …and followed for a number of years (this is where the term “prospective” comes from)…
  • …and at the end of the study, the association between food and heart outcomes is measured.

However, the review also included several major randomized controlled clinical trials, including:

  • The DASH diet study.
  • The Lyon Diet Heart study.
  • The PREDIMED study.

Give Your Heart A Valentine

What is a heart-healthy diet? Here are the findings of the study. Most will sound very familiar. But you will note strong heartsome subtle differences based on recent data.

The overall summary was that for a healthy adult population:

  • Low consumption of salt and foods of animal origin…
  • …and increased intake of plant foods…
  • …are associated with reduced heart disease risk.

Of course, we have known that for years. It’s when they broke the data down further that it became more interesting.

Foods Of Animal Origin:

  • Processed meats increase heart disease risk. A single serving of processed meat is associated with a 27% to 44% increased risk of heart disease. This is not new.
  • Unprocessed red meat is also associated with increased risk of heart disease, but this association is not as consistent as for processed meats. The authors noted that some of this may be due to differences in saturated fat content or cooking methods of the red meats included in individual studies.

But this analysis also showed that the effect of red meat on heart disease risk may be dose dependent. For example:

    • The studies they reviewed suggested that consuming ≥3 servings per day of red meat is associated with a 27% increased risk of heart disease. However, consuming <3 servings per week may not increase risk, especially when consumed in the context of an otherwise heart-healthy diet.
  • White meat such as poultry does not appear to affect heart disease risk. This has been predicted by earlier reports, but this analysis strengthens those predictions.
  • Fish consumption decreases heart disease risk. This is not new. But this review added precision about recommended fish intake (2-4 servings/week) and a couple of caveats:
    • The heart benefits of fish may be due to their omega-3 content and may not apply equally to fish with lower omega-3 content.
    • The authors also expressed concerns about the sustainability of high-omega-3 fish populations. I would also add that our oceans are increasingly polluted, so contamination is another concern.
  • Egg consumption up to one egg/day does not appear to increase heart disease risk. This is consistent with the current American Heart Association recommendations.

However, the authors noted that the effect of eggs on serum cholesterol, and hence heart disease risk depends on several factors.

    • Genetics, obesity, and diabetes can make it more difficult to regulate serum cholesterol levels. For these individuals, eggs may need to be eaten only sparingly.
    • Diets low in saturated fat and high in fiber from plant foods help the body regulate serum cholesterol. Several studies suggest that eggs may decrease heart disease risk in the context of this type of a heart-healthy diet.
  • Dairy: Neither low-fat nor high-fat dairy foods appear to influence heart disease risk. This is different from the standard recommendation to consume low-fat dairy foods. But it is in line with the trend of recent research studies on dairy and heart disease.

Once again, there were a couple of caveats:

    • There is increasing evidence that fermented dairy foods may decrease heart disease risk which may explain why certain high-fat cheeses and other high-fat fermented dairy foods appear to have a neutral or slightly beneficial effect on heart disease risk.
    • As with eggs, the effect of high-fat dairy foods on heart disease risk may be influenced by genetics and diet context.

Vegan FoodsFoods Of Plant Origin: The effects of plant foods on heart health have been known for some time, and the most recent studies included in this analysis have not changed those conclusions.

  • Fruits and Vegetables consistently reduce heart disease risk in multiple studies. In each case, the optimal intake appears to be about 2 servings of each per day which provides an 18-21% risk reduction for vegetables and a 21-32% risk reduction for fruits.
  • Legumes (beans and peas) also consistently reduce heart disease risk in multiple studies. At the optimal intake of around 4 servings per week the risk reduction is around 14%.
  • Nuts also consistently reduce heart disease risk. At the optimal intake of around one serving (a handful) per day, the risk reduction is around 25%.
  • Cereals (grains) were divided into 3 categories:
    • Refined carbohydrates with a high glycemic index (e.g., white rice, white bread) are associated with increased heart disease risk in multiple studies probably due to their effect on blood sugar levels. And the increased risk is significant (Around 66% higher risk for every 2 servings).
    • Refined carbohydrates with a low glycemic index (e.g., pasta, corn tortillas) show an inconsistent effect on heart disease risk.
    • Whole grains are consistently associated with a lower heart disease risk. Two servings of whole grains per day are associated with a 25%-34% decreased risk.

Miscellaneous Foods:

  • Soft Drinks are associated with increased heart disease risk. One serving per day increases the risk by around 15-22% and recent evidence suggests that artificially sweetened soft drinks offer no heart health benefits compared to sugar sweetened soft drinks.
  • Coffee and Tea are both associated with decreased heart disease risk. For coffee the optimal benefit may occur at around 3 cups/day. Higher levels may have an adverse effect on heart disease risk.

Summary of Heart Health Recommendations

ScientistIf you think that was a lot of information, the authors provided a numerical summary of their recommendations for a heart-healthy diet. They are:

  • Two servings per day of vegetables, fresh fruits, and whole grains.
  • One serving per day of nuts and seeds, low-glycemic index refined cereals, extra-virgin olive oil or non-tropical vegetable oils, and yogurt.
  • Four servings per week of legumes and fish.
  • No more than 3 servings per week of white meat, eggs, cheese, and milk.
  • No more than 2 servings per week of high-glycemic index refined starchy foods, red meat, and butter.
  • Only occasional consumption of processed meats.

How Can You Give Your Heart A Valentine?

Of course, nobody wants to follow a “diet by the numbers”. If you are like most of us, you want flexibility and you Questionswant to be able to eat some of your favorite foods. So, let me put these recommendations into a more “user friendly” form.

If you want to give your heart a valentine:

  • Whole, unprocessed or minimally processed, plant foods are your heart’s best friends.
  • Your heart-healthy foundation should be fruits, vegetables, whole grains, nuts and seeds, healthy plant oils, and legumes.
    • Your heart-healthy foundation can also include fermented dairy foods and low-glycemic index refined grains.
    • Your “go-to” beverages should be water, tea (both caffeinated and herbal teas), and coffee. You should avoid soft drinks and other sugar-sweetened or artificially sweetened beverages.
  • Once you have achieved a heart-healthy foundation you can add a few servings per week of white meat, eggs, cheese, and dairy, even high-fat dairy.
    • If you have good adherence to the heart-healthy foundation described above and no genetic or health issues that increase your risk of heart disease, you can probably eat more of these foods.
    • Conversely, if your adherence to the heart-healthy foundation is poor and/or you are at high risk of heart disease, you may wish to consume less of these foods.
  • If you have good adherence to the heart-healthy foundation, you can also add up to 1-2 servings of high-glycemic index refined carbohydrates, red meat, or butter per week. With red meat, you may want to consider it as a garnish that adds flavor to a plant-based meal rather than the centerpiece of the meal.
    • You should eat processed meats seldom or never.

This would be the best Valentine’s gift you could possibly give your heart.

The Bottom Line

For those of you who might want to give your heart a valentine, a new comprehensive review and meta-analysis of 99 clinical studies with tens of thousands of participants has updated the correlation between foods and heart disease risk.

Many of the recommendations based on this analysis are identical to previous recommendations for a heart-healthy diet.

But there are some subtle changes to those recommendations based on the latest data.

For more details about this study and what a heart-healthy diet might look like 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.

______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.

Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”.

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 54 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

 

 

 

 

Eating For A Healthy Heart

by

What Does This Mean For You?

Author: Dr. Stephen Chaney

You may remember the nursery rhyme, “Jack Sprat could eat no fat. His wife could eat no lean…” You may know people who fit these extremes. And in terms of diets these extremes might represent the vegan and keto diets in today’s world.

The nursery rhyme assures us that, “…between them they licked the platter clean.” But were their diets equally healthy? Which of them would have been more likely to live a long and healthy life?

And, since this is Heart Health Month, we might ask, “Which diet would have been better for their hearts?”

If you search Mr. Google – even with AI assist – you might be confused. That’s because AI bases its recommendations on the quantity of posts, not the accuracy of posts. And lots of media influencers recommend both diets, and just about every popular diet in between for heart health.

But what does good science say on the topic of heart healthy diets? Fortunately, a recent comprehensive review and meta-analysis (G. Riccardi et al, Cardiovascular Research, 118: 1118-1204, 2022) has answered that question.

How Was The Study Done?

clinical studyThe investigators reviewed 99 clinical studies with tens of thousands of participants that looked at the associations between foods or food groups and heart disease risk.

Most of the studies were “prospective cohort” studies in which:

  • Populations are divided into groups (cohorts) based on the foods they consume…
  • …and followed for a number of years (this is where the term “prospective” comes from)…
  • …and at the end of the study, the association between food and heart outcomes is measured.

However, the review also included several major randomized controlled clinical trials, including:

  • The DASH diet study.
  • The Lyon Diet Heart study.
  • The PREDIMED study.

Eating For A Healthy Heart

strong heartHere are the findings of the study. Most will sound very familiar. But you will note some subtle differences based on recent data.

The overall summary was that for a healthy adult population:

  • Low consumption of salt and foods of animal origin…
  • …and increased intake of plant foods…
  • …are associated with reduced heart disease risk.

Of course, we have known that for years. It’s when they broke the data down further that it became more interesting.

Foods Of Animal Origin:

  • Processed meats increase heart disease risk. A single serving of processed meat is associated with a 27% to 44% increased risk of heart disease. This is not new.
  • Unprocessed red meat is also associated with increased risk of heart disease, but this association is not as Steakconsistent as for processed meats. The authors noted that some of this may be due to differences in saturated fat content or cooking methods of the red meats included in individual studies.

But this analysis also showed that the effect of red meat on heart disease risk may be dose dependent. For example:

    • The studies they reviewed suggested that consuming ≥2 servings per day of red meat is associated with a 27% increased risk of heart disease. However, consuming <3 servings per week may not increase risk.
    • The idea that the effect of red meat on heart disease risk may be dose-dependent is novel. However, the authors said we also need to ask what replaces red meat in the diet. They postulated that when red meat consumption is decreased, it is often replaced with healthier protein sources.
  • White meat such as poultry does not appear to affect heart disease risk. This has been predicted by earlier reports, but this analysis strengthens those predictions.
  • Fish consumption decreases heart disease risk. This is not new. But this review added precision about recommended fish intake (2-4 servings/week) and a couple of caveats:
    • The heart benefits of fish may be due to their omega-3 content and may not apply equally to fish with lower omega-3 content.
    • The authors also expressed concerns about the sustainability of high-omega-3 fish populations. I would also add that our oceans are increasingly polluted, so contamination is another concern.
  • Egg consumption up to one egg/day does not appear to increase heart disease risk. This is consistent with the are eggs good for youcurrent American Heart Association recommendations.

However, the authors noted that the effect of eggs on serum cholesterol, and hence heart disease risk depends on several factors.

    • Genetics, obesity, and diabetes can make it more difficult to regulate serum cholesterol levels. For these individuals, eggs may need to be eaten only sparingly.
    • Diets low in saturated fat and high in fiber from plant foods help the body regulate serum cholesterol. Several studies suggest that eggs may decrease heart disease risk in the context of this type of diet.
  • Dairy: Neither low-fat nor high-fat dairy foods appear to influence heart disease risk. This is different from the standard recommendation to consume low-fat dairy foods. But it is in line with the trend of recent research studies on dairy and heart disease.

Once again, there were a couple of caveats:

    • There is increasing evidence that fermented dairy foods may decrease heart disease risk which may explain why certain high-fat cheeses and other high-fat fermented dairy foods appear to have a neutral or slightly beneficial effect on heart disease risk.
    • As with eggs the effect of high-fat dairy foods on heart disease risk may be influenced by genetics and diet context.

Foods Of Plant Origin: The effect of plant foods have been known for some time, and the most recent studies included in this analysis have not changed those conclusions.

  • Fruits and Vegetables consistently reduce heart disease risk in multiple studies. In each case, the optimal Vegan Foodsintake appears to be about 2 servings of each per day which provides an 18-21% risk reduction for vegetables and a 21-32% risk reduction for fruits.
  • Legumes (beans and peas) also consistently reduce heart disease risk in multiple studies. At the optimal intake of around 4 servings per week the risk reduction is around 14%.
  • Nuts also consistently reduce heart disease risk. At the optimal intake of around one serving (a handful) per day, the risk reduction is around 25%.
  • Cereals (grains) were divided into 3 categories:
    • Refined carbohydrates with a high glycemic index (e.g., white rice, white bread) are associated with increased heart disease risk in multiple studies probably due to their effect on blood sugar levels. And the increased risk is significant (Around 66% higher risk for every 2 servings).
    • Refined carbohydrates with a low glycemic index (e.g., pasta, corn tortillas) show an inconsistent effect on heart disease risk.
    • Whole grains are consistently associated with a lower heart disease risk. Two servings of whole grains per day are associated with a 25%-34% decreased risk.

Miscellaneous Foods:

  • Soft Drinks are associated with increased heart disease risk. One serving per day increases the risk by around 15-22% and recent evidence suggests that artificially sweetened soft drinks offer no heart health benefits compared to sugar sweetened soft drinks.
  • Coffee and Tea are both associated with decreased heart disease risk. For coffee the optimal benefit may occur at around 3 cups/day. Higher levels may have an adverse effect on heart disease risk.

Summary of Heart Health Recommendations

ScientistIf you are thinking that was a lot of information, the authors provided a numerical summary of their recommendations for a heart-healthy diet. They are:

  • Two servings per day of vegetables, fresh fruits, and whole grains.
  • One serving per day of nuts and seeds, low-glycemic index refined cereals, extra-virgin olive oil or non-tropical vegetable oils, and yogurt.
  • Four servings per week of legumes and fish.
  • No more than 3 servings per week of white meat, eggs, cheese, and milk.
  • No more than 2 servings per week of high-glycemic index refined starchy foods, red meat, and butter.
  • Only occasional consumption of processed meats.

What Does This Study Mean For You?

QuestionsOf course, nobody wants to follow a “diet by the numbers”. If you are like most of us, you want flexibility and you want to be able to eat some of your favorite foods. So, let me put these recommendations into a more “user friendly” form.

If you want a healthy heart:

  • Whole, unprocessed or minimally processed, plant foods are your friends.
  • Your heart-healthy foundation should be fruits, vegetables, whole grains, nuts and seeds, healthy plant oils, and legumes.
  • Your heart-healthy foundation can also include fermented dairy foods and low-glycemic index refined grains.
  • Your “go-to” beverages should be water, tea (both caffeinated and herbal teas), and coffee. You should avoid soft drinks and other sugar-sweetened or artificially sweetened beverages.
  • Once you have achieved a heart-healthy foundation you can add a few servings per week of white meat, eggs, cheese, and dairy, even high-fat dairy.
  • If you have good adherence to the heart-healthy foundation described above and no genetic or health issues that increase your risk of heart disease, you can probably eat more of these foods.
  • Conversely, if your adherence to the heart-healthy foundation is poor and/or you are at high risk of heart disease, you may wish to consume less of these foods.
  • If you have good adherence to the heart-healthy foundation, you can also add up to 1-2 servings of high-glycemic index refined carbohydrates, red meat, or butter per week. With red meat, you may want to consider it as a garnish that adds flavor to a plant-based meal rather than the centerpiece of the meal.
  • You should eat processed meats seldom or never.

The Bottom Line

A new comprehensive review and meta-analysis of 99 clinical studies with tens of thousands of participants has updated the correlation between foods and heart disease risk.

Many of the recommendations based on this analysis are identical to previous recommendations for a heart-healthy diet.

But there are some subtle changes to those recommendations based on the latest data.

For more details about this study and what a heart-healthy diet might look like 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.

_______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Can Unhealthy Eating Give You Colon Cancer?

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What Are Ultra-Processed Foods, And Why Might They Cause Colon Cancer? 

Author: Dr. Stephen Chaney 

The new year is almost here. If you are like millions of Americans, you may already be making a list of potential New Year’s resolutions and “checking it twice”. If weight loss and a healthier diet are important to you, you may want to put cutting back on ultra-processed foods at the top of your list.

And that’s not easy to do. We love our junk foods and our convenience foods.

  • It’s so easy to just stop by the nearest drive-through to pick up a quick meal. And we are hardwired to desire sweet, salty, and fatty foods. That’s why we love the taste of junk foods.
  • We lead busy lives. It’s easier and quicker to pop prepackaged foods into the microwave or oven than prepare a meal from scratch.
  • Even when we go on a diet to lose weight or improve our health, we want quick and easy. And “Big Food Inc” is only too happy to grant us our wish. They offer ultra-processed meals for every weight loss plan and diet program.
  • Many of us are second or third generation junk and convenience food lovers. Junk and convenience foods have become normal. Ultra-processed foods now make up 57% of the daily calories consumed by most Americans.
    • For example, my mother believed in a balanced diet as long as the foods came from a can or a box. That was normal for me growing up. If my wife had not been brought up very differently, I would not be nearly as healthy as I am today.

Unfortunately, it is becoming increasingly clear that ultra-processed foods are bad for us. In recent issues of “Health Tips From the Professor” I have shared studies suggesting that ultra-processed foods make us fat, increase our risk of diabetes, and increase our risk of cancer. And if that weren’t bad enough, ultra-processed foods give us gas.

The cancer study referenced above showed that ultra-processed foods increased the risk of overall cancer and breast cancer but did not break it down into other kinds of cancer.

Colon cancer ranks third in overall cancers and second in cancer deaths for both men and women. And foods like processed meats are thought to increase the risk of colon cancer. This inspired the authors of a recent study to ask whether ultra-processed foods increased the risk of colon cancer.

What Are Ultra-processed Foods, And Why Might They Cause Colon Cancer?

Fast Food ExamplesUltra-processed foods:

  • Usually go through several physical and chemical processes, such as extruding, molding, prefrying, and hydrogenation that can lead to the formation of toxic carcinogens that may increase the risk of colon cancer.
    • One example you may have heard about recently would be acrylamide in French fries. Another example would be nitrosamines in processed meats.
  • Are usually high in added sugar, fat, and refined starch which contribute to increased weight gain and obesity, an established risk factor for colon cancer.
  • Are usually low in phytonutrients, fiber, calcium, and vitamin D, which are known to reduce the risk of colon cancer
  • Typically contain ingredients of little or no nutritive value, such as refined sugar, hydrogenated oils, emulsifiers, artificial sweeteners, thickening agents, and artificial colors. Some of these ingredients, such as emulsifiers and artificial sweeteners, have been suggested to cause inflammation in the intestine, which is known to increase the risk of colon cancer.
  • Have long shelf-lives because of added preservatives. This allows migration of carcinogens such as bisphenol A from the packaging materials into the food.

Examples of ultra-processed foods include:

  • Sodas
  • Chips
  • Candy and packages of cookies or crackers
  • Most breakfast cereals
  • Boxed cake, cookie, and pancake mix
  • Chicken nuggets and fish sticks
  • Fast food burgers
  • Hot dogs and other processed meat
  • Infant formula
  • Instant noodles
  • Most store-bought ice cream
  • Flavored yogurt

How Was This Study Done?

clinical studyThis study used data collected from:

  • The Nurses’ Health Study (NHS) which enrolled 121,700 female nurses aged 30-55 in 1976 and followed them for 28 years.
  • The Nurses’ Health Study II (NHS II) which enrolled 116,429 female nurses aged 25-42 in 1989 and followed them for 24 years.
  • The Health Professions’ Follow-up Study (HPFS) which enrolled 51,529 male health professionals aged 40-75 in 1986 and followed them for 28 years.

After excluding participants who had incomplete data or a previous cancer diagnosis, the investigators running the study ended up with 67,425 women from NHS, 92,482 women from NHS II, and 46,341 men from HPFS for analysis.

Ultra-processed food consumption was scored as follows:

  • The dietary intake of each participant in the studies was assessed with a food frequency questionnaire every four years.
  • Each questionnaire was scored for the percentage of ultra-processed foods.
  • Then each participant in the study was ranked in terms of the percent ultra-processed foods in their diet averaged over the entire time they were enrolled in the study.
  • The participants were then divided into 5 groups based on the number of servings of ultra-processed foods/day they consumed, ranging from a high of 9 servings/day to a low of 3 servings/day.

Every two years the participants were asked to report any cancer diagnosis in the previous two years. Study physicians reviewed the medical records and pathology reports to confirm a diagnosis of colon cancer. If the patient had died, death certificates and medical records were used to confirm a diagnosis of colon cancer.

The investigators then compared the incidence of colon cancer in the group consuming the most ultra-processed foods to the group consuming the least ultra-processed foods.

  • These comparisons were adjusted for compounding factors like race, family history of cancer, history of endoscopy, physical activity, smoking status, alcohol use, aspirin use, menopausal status, and post-menopausal hormone use.
  • The comparisons were also adjusted for obesity and a healthy diet score called AHEI. I will explain the significance of these adjustments below.
  • Finally, the investigators looked at how various categories of ultra-processed food influenced the results.

Can Unhealthy Eating Give You Colon Cancer?

colon cancerHere is what the study found:

  • Men in the highest fifth of ultra-processed food consumption had a 29% higher risk of developing colon cancer than those in the lowest fifth.
  • No association between ultra-processed food consumption and risk of developing colon cancer was seen for women.

When they looked at subgroups of ultra-processed foods again comparing the top fifth in consumption with the lowest fifth:

  • Consumption of ultra-processed ready to eat products containing meat, poultry, or seafood increased the risk of colon cancer by 44% in men and 14% in women.
  • Consumption of sugar-sweetened beverages increased the risk of colon cancer by 21% in men but did not significantly affect risk of colon cancer in women.
  • Consumption of ultra-processed ready to eat mixed dishes increased the risk of colon cancer by 17% in women but did not significantly affect risk of colon cancer in men.
  • Consumption of ultra-processed dairy products decreased the risk of colon cancer by 17% in women but did not significantly affect risk of colon cancer in men.

The reason for the differing effect of poor diet on the risk of colon cancer in men and women is not clear, but it has been observed in previous studies.

The investigators concluded, “…high consumption of total ultra-processed foods in men and certain subgroups of ultra-processed foods in men and women was associated with an increased risk of colorectal cancer. Further studies are needed to better understand the potential attributes of ultra-processed foods that contribute to colorectal carcinogenesis.”

What Does This Study Mean For You?

There are several take-home lessons from this study:

1: The 29% increase in colon cancer risk reported for men probably underestimates the true risk. I say that because:

  • Ultra-processed food consumption increases the likelihood that you will gain weight, and obesity is a known risk factor for colon cancer. However, the 29% number was obtained after adjusting the data for obesity. Without that adjustment the increased risk would have been greater
  • Ultra-processed foods are low in the protective phytonutrients and fiber provided by fruits, vegetables, and whole grains. However, the 29% number was obtained after adjusting the data for a healthy eating index (which includes the amounts of fruits, vegetables, and whole grains in the diet). Without that adjustment the increased risk would have been greater.

2: While we don’t know the mechanism(s) for the increased risk of colon cancer reported in this study, we can make some informed guesses. I say that because:

  • Once you have removed obesity and fruits, vegetables, and whole grains from consideration, you are left with:
    • The effect of ultra-processed foods on your gut bacteria.
    • The additives, preservatives, and other potentially carcinogenic chemicals in ultra-processed foods.

3: Finally, don’t think you are off the hook if you are a woman.

  • As I mentioned in the introduction, ultra-processed foods also increase your risk of obesity, diabetes, and breast cancer.

And that brings us back to what I said at the beginning of this article, “If you are like millions of Americans, you may already be making a list of New Year’s resolutions and “checking it twice”. If weight loss and a healthier diet are important to you, you may want to put cutting back on ultra-processed foods at the top of your list.”

The Bottom Line 

A recent study showed that ultra-processed food consumption increased the risk of colon cancer in men, but not in women. The reason for the differing effect of ultra-processed foods on the risk of colon cancer in men and women is not clear, but it has been observed in previous studies on the effect of poor diet on colon cancer risk.

However, don’t think you are off the hook if you are a woman. Previous studies have shown that ultra-processed food consumption increased the risk of obesity, diabetes, and total cancers in both men and women and the risk of breast cancer in women.

The investigators concluded, “…high consumption of total ultra-processed foods in men and certain subgroups of ultra-processed foods in men and women was associated with an increased risk of colorectal cancer.”

That brings me to my recommendation. “If you are like millions of Americans, you may already be making a list of potential New Year’s resolutions and “checking it twice”. If weight loss and a healthier diet are important to you, you may want to put cutting back on ultra-processed foods at the top of your list.”

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 Protect Your Mind?

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Which Diet Is Best?

Author: Dr. Stephen Chaney 

can diet prevent alzheimer'sAlzheimer’s is a scary disease. There is so much to look forward to in our golden years. We want to enjoy the fruits of our years of hard work. We want to enjoy our grandkids and perhaps even our great grandkids. More importantly, we want to be able to pass on our accumulated experiences and wisdom to future generations.

Alzheimer’s and other forms of dementia have the potential to rob us of everything that makes life worth living. What is the use of having a healthy body, family, and fortune if we can’t even recognize the people around us?

Alzheimer’s and other forms of dementia don’t happen overnight. The first symptoms of cognitive decline are things like forgetting names, where you left things, what you did last week. For most people it just keeps getting worse.

Can diet protect your mind? Recent studies have given us a ray of hope. For example, several meta-analyses have shown that adherence to the Mediterranean diet was associated with a 25-48% lower risk of cognitive decline and dementia.

However, there were several limitations to the studies included in these meta-analyses. For example:

  • For most of the studies the diet was assessed only at the beginning of the study. We have no idea whether the participants followed the same diet throughout the study. This means, we cannot answer questions like:
    • What is the effect of long-term adherence to a healthy diet?
    • Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet?
  • These studies focused primarily on the Mediterranean diet. This leaves the question:
    • What about other healthy diets? Is there something unique about the Mediterranean diet, or do other healthy diets also reduce the risk of cognitive decline?

This study (C Yuan et al, American Journal of Clinical Nutrition, 115: 232-243, 2022) was designed to answer those questions.

How Was The Study Done?

clinical studyThe investigators utilized data from The Nurse’s Health Study. They followed 49,493 female nurses for 30 years from 1984 to 2014. The average age of the nurses in 1984 was 48 years, and none of them had symptoms of cognitive decline at the beginning of the study.

The nurse’s diets were analyzed in 1984, 1986, and every 4 years afterwards until 2006. Diets were not analyzed during the last 8 years of the study to eliminate something called “reverse causation”. Simply put, the investigators were trying to eliminate the possibility that participants in the study might change their diet because they were starting to notice symptoms of cognitive decline.

The data from the dietary analyses were used to calculate adherence to 3 different healthy diets:

  • The Mediterranean diet.
  • The DASH diet. The DASH diet was designed to reduce the risk of high blood pressure. But you can think of it as an Americanized version of the Mediterranean diet.
  • The diet recommended by the USDA. Adherence to this diet is evaluated by something called the Alternative Healthy Eating Index or AHEI.

Adherence to each diet was calculated by giving a positive score to foods that were recommended for the diet and a negative score for foods that were not recommended for the diet. For more details, read the article.

In 2012 and 2014 the nurses were asked to fill out questionnaires self-assessing the early stages of cognitive decline. They were asked if they had more trouble than usual:

  • Remembering recent events or remembering a short list of items like a grocery list (measuring memory).
  • Understanding things, following spoken instructions, following a group conversation, or following a plot in a TV program (measuring executive function).
  • Remembering things from one second to the next (measuring attention).
  • Finding ways around familiar streets (measuring visuospatial skills).

The extent of cognitive decline was calculated based on the number of yes answers to these questions.

Can Diet Protect Your Mind?

Vegan FoodsHere is what the investigators found when they analyzed the data:

At the beginning of the study in 1984 there were 49,493 female nurses with an average age of 48. None of them had symptoms of cognitive decline.

  • By 2012-2014 (average age = 76-78) 46.9% of them had cognitive decline and 12.3% of them had severe cognitive decline.

Using the data on dietary intake and the rating systems specific to each of the diets studied, the investigators divided the participants into thirds based on their adherence to each diet. The investigators then used these data to answer two important questions that no previous study had answered:

#1: What is the effect of long-term adherence to a healthy diet? To answer this question the investigators averaged the dietary data obtained every 4 years between 1984 and 2006 to obtain cumulative average scores for adherence to each diet. When the investigators compared participants with the highest adherence to various healthy diets for 30 years to participants with the lowest adherence to those diets, the risk of developing severe cognitive decline was decreased by:

  • 40% for the Mediterranean diet.
  • 32% for the DASH diet.
  • 20% for the USDA-recommended healthy diet (as measured by the AHEI score).

#2: Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet? To answer this question, the investigators looked at participants who started with the lowest adherence to each diet and improved to the highest adherence by the end of the study. This study showed that improving from an unhealthy diet to a healthy diet over 30 years decreased the risk of developing severe cognitive decline by:

  • 20% for the Mediterranean diet.
  • 25% for the DASH diet.

There were a few other significant observations from this study.

  • The inverse association between healthy diets and risk of cognitive decline was greater for nurses who had high blood pressure.
    • This is an important finding because high blood pressure increases the risk of cognitive decline.
  • The inverse association between healthy diets and risk of cognitive decline was also greater for nurses who did not have the APOE-ɛ4 gene.
    • This illustrates the interaction of diet and genetics. The APOE-ɛ4 gene increases the risk of cognitive decline. Healthy diets reduced the risk of cognitive decline in nurse with the APOE-ɛ4 gene but not to the same extent as for nurses without the gene.

This study did not investigate the mechanism by which healthy diets reduced the risk of cognitive decline, but the investigators speculated it might be because these diets:

  • Were anti-inflammatory.
  • Supported the growth of healthy gut bacteria.

The investigators concluded, “Our findings support the beneficial roles of long-term adherence to the [Mediterranean, DASH, and USDA] dietary patterns for maintaining cognition in women…Further, among those with initially relatively low-quality diets, improvement in diet quality was associated with a lower likelihood of developing severe cognitive decline. These findings indicate that improvements in diet quality in midlife and later may have a role in maintenance of cognitive function among women.”

Which Diet Is Best?

Mediterranean Diet FoodsIn a sense this is a trick question. That’s because this study did not put the participants on different diets. It simply analyzed the diets the women were eating in different ways. And while the algorithms they were using were diet-specific, there was tremendous overlap between them. For more specifics on the algorithms used to estimate adherence to each diet, read the article.

That is why the investigators concluded that all three diets they analyzed reduced the risk of cognitive decline rather than highlighting a specific diet. However, based on this and numerous previous studies the evidence is strongest for the Mediterranean and DASH diets.

And I would be remiss if I didn’t also mention the MIND diet. While it was not included in this study, the MIND diet:

  • Was specifically designed to reduce cognitive decline.
  • Can be thought of as a combination of the Mediterranean and DASH diets.
  • Includes data from studies on the mind-benefits of individual foods. For example, it recommends berries rather than all fruits.

The MIND diet has not been as extensively studied as the Mediterranean and DASH diets, but there is some evidence that it may be more effective at reducing cognitive decline than either the Mediterranean or DASH diets alone.

Which Foods Are Best?

AwardThe authors of this study felt it was more important to focus on foods rather than diets. This is a better approach because we eat foods rather than diets. With that in mind they analyzed their data to identify the foods that prevented cognitive decline and the foods increased cognitive decline. This is what they found:

  • Fruits, fruit juices, vegetables, fish, nuts, legumes, low-fat dairy, and omega-3 fatty acids (fish oil) reduced the risk of cognitive decline.
  • Red and processed meats, omega-6 fatty acids (most vegetable oils), and trans fats increased the risk of cognitive decline.

While this study did not specifically look at the effect of processed foods on cognitive decline, diets high in the mind-healthy foods listed above are generally low in sodas, sweets, and highly processed foods.

What Does This Study Mean For You?

Question MarkThe question, “Can diet protect your mind”, is not a new one. Several previous studies have suggested that healthy diets reduce the risk of cognitive decline, but this study breaks new ground. It shows for the first time that:

  • Long-term adherence to a healthy diet can reduce your risk of cognitive decline by up to 40%.
    • This was a 30-year study, so we aren’t talking about “diet” in the traditional sense. We aren’t talking about short-term diets to drop a few pounds. We are talking about a life-long change in the foods we eat.
  • If you currently have a lousy diet, it’s not too late to change. You can reduce your risk of cognitive decline by switching to a healthier diet.
    • This is perhaps the best news to come out of this study.

Based on current evidence, the best diets for protecting against cognitive decline appear to be the Mediterranean, DASH, and MIND diets.

And if you don’t like restrictive diets, my advice is to:

  • Eat more fruits, fruit juices, vegetables, fish, nuts, legumes, low-fat dairy, and omega-3 fatty acids (fish oil).
  • Eat less red and processed meats, omega-6 fatty acids (most vegetable oils), and trans fats.
  • Eat more plant foods and less animal foods.
  • Eat more whole foods and less sodas, sweets, and processed foods.

And, of course, a holistic approach is always best. Other lifestyle factors that help reduce your risk of cognitive decline include:

  • Regular exercise.
  • Weight control.
  • Socialization.
  • Memory training (mental exercises).

The Bottom Line 

Alzheimer’s is a scary disease. What is the use of having a healthy body, family, and fortune if we can’t even recognize the people around us?

A recent study looked at the effect of diet on cognitive decline in women. The study started with middle-aged women (average age = 48) and followed them for 30 years. The investigators then used these data to answer two important questions that no previous study had answered:

#1: What is the effect of long-term adherence to a healthy diet? When the investigators compared participants with the highest adherence to various healthy diets for 30 years to participants with the lowest adherence to those diets, the risk of developing severe cognitive decline was decreased by:

  • 40% for the Mediterranean diet.
  • 32% for the DASH diet.
  • 20% for the USDA recommendations for a healthy diet.

#2: Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet? This study showed that improving from an unhealthy diet to a healthy diet over 30 years decreased the risk of developing severe cognitive decline by:

  • 20% for the Mediterranean diet.
  • 25% for the DASH diet.

The investigators concluded, “Our findings support the beneficial roles of long-term adherence to the [Mediterranean, DASH, and USDA] dietary patterns for maintaining cognition in women…Further, among those with initially relatively low-quality diets, improvement in diet quality was associated with a lower likelihood of developing severe cognitive decline. These findings indicate that improvements in diet quality in midlife and later may have a role in maintenance of cognitive function among women.”

For more details on the study, which diets, and which foods are best for protecting your mind, and 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.

Does Processed Food Give You Gas?

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Why Does Processed Food Give You Gas?

Author: Dr. Stephen Chaney 

Does it feel like a war is going on in your belly every time you eat? It could be IBD (inflammatory bowel disease). IBD can take several forms, but the two most common are Crohn’s disease and ulcerative colitis.

What do we know about IBD?

  • The symptoms of IBD can make you miserable. They include:
    • Abdominal pain and cramping.
    • Diarrhea with occasional bouts of constipation.
    • Gas and bloating.
    • Loss of appetite and/or unexpected weight loss.
  • There are about 1.6 million Americans with IBD and 70,000 new cases/year.
    • The prevalence of IBD in the United States has increased by 34% between 2006 and 2016.
  • As you might suspect from its name, IBD is a chronic inflammation of the gastrointestinal tract.
    • It is thought to be caused by “dysbiosis of the gastrointestinal track” (In layman’s terms that means damage to your intestine caused by too many bad bacteria and not enough good bacteria).
    • There is also a genetic component to the disease. Some people are much more susceptible to IBD than others.

If you watch TV, you know that there are drugs for treating IBD. The ads make them sound like miracle drugs. But if you listen carefully, you also know that these drugs have a long list of side effects. And some of the side effects are pretty scary.

Are There Natural Approaches For Controlling IBD?

BacteriaSo, if your belly is a bit rumbly, you might be wondering if there is a more natural approach you could take. We know that diet affects the balance between bad and good bacteria in our intestine. Could something as simple as changing your diet, quell the fire in your belly?

While the answer seems obvious, it has been hard to prove. The results of previous studies have been inconclusive. That is because previous studies:

  • Included too few people. 1.6 million people in the US with IBD may sound like a lot, but that represents only 0.4% of the population. Unless you have a really big study, there won’t be enough people who develop IBD to give you statistically significant results.
  • Were too short. IBD doesn’t develop overnight.
  • Did not include a diverse enough population. Previous studies were confined to individual countries or specific regions within a country.

This study (N Narula et al, British Medical Journal, 2021;374:n1554) was designed to overcome the limitations of previous studies. It also looked at the effect of diet on IBD from a different perspective than most previous studies.

  • It did not focus on the effect of individual foods on IBD. Since consumption of processed foods is known to affect the population of intestinal bacteria, the authors of this study asked whether processed food consumption might influence the likelihood of developing IBD.

How Was The Study Done?

Clinical StudyThe authors of this study used data collected from the PURE (Prospective Urban Rural Epidemiology) study between January 1, 2003, and December 31, 2016. The PURE study collected data from a very diverse population. Specifically, it collected data from 21 low-, middle-, and high-income countries across 7 geographical regions (Europe, North America, South America, Africa, Middle East, South Asia, Southeast Asia, and China).

  • This study followed 116,087 adults aged 35-70 years (average age 50, percent women = 60%) in the PURE study for an average of 9.7 years. During that time, 467 participants (0.4%) developed IBD.
  • All participants filled out a baseline food-frequency questionnaire that had been designed and validated for foods specific to their country.
  • Participants were asked if they had a diagnosis of Crohn’s disease or ulcerative colitis as part of an annual follow-up questionnaire. To assure the accuracy of these answers they were validated with medical records whenever possible.

Does Processed Food Give You Gas?

Does processed food give you gas? Does it give you abdominal pain, diarrhea, and bloating? In short, does it give you IBD? That is the question this study was designed to answer. Here are the results of the study:

  • When comparing those eating the most processed food (≥5 servings/day) to those consuming the least (≤1 serving/day), processed food consumption increased the risk of developing IBD by 1.82-fold. This finding was equally true for:
    • Both Crohn’s disease and ulcerative colitis.
    • Adults <50 and adults >50.
    • Every region of the world included in the PURE study.
  • When the investigators looked at different categories of processed foods:
    • Processed meat intake increased the risk of IBD by 2.07-fold.
    • Soft drink intake increased the risk of IBD by 1.94-fold.
    • Refined sweetened food intake increased the risk of IBD by 2.58-fold.
    • Salty food and snack intake increased the risk of IBD by 2.06-fold.
  • When the investigators looked at different categories of unprocessed foods:
    • White meat, red meat, dairy, starchy foods, fruits, vegetables, and legumes had no effect on the risk of developing IBD.
    • Sodium intake (as measured by urinary excretion of sodium) also had no effect on the risk of developing IBD.

Why Does Processed Food Give You Gas?

Question MarkYou may be wondering why does processed food give you gas – and other symptoms of IBD.

The simplest explanation is that whole grains, unprocessed fruits & vegetables, and legumes provide the fiber that supports the growth of friendly gut bacteria. Processed foods displace these foods from our diet.

But these investigators think something else about processed foods may be contributing to the increased risk of IBD. That is because in their study:

  • Processed meat increased the risk of IBD, but unprocessed white and red meat had no effect on IBD.
  • Processed sweetened foods increased the risk of IBD, but unprocessed starchy foods and naturally sweet fruits had no effect on IBD.
  • Processed salty foods and snacks increased the risk of IBD, but sodium intake had no effect on IBD.

The investigators also noted that in mouse studies:

  • Some food additives found in processed foods cause bacteria to stick to the epithelial lining of the intestine and/or cause leaky gut syndrome, both of which can lead to chronic inflammation of the intestine.

The investigators concluded, “In this study, higher ultra-processed food intake was associated with a higher risk of IBD.”

They went on to say, “As white meat, unprocessed red meat, dairy, starchy foods, fruits, vegetables, and legumes were not found to be associated with development of IBD, this study suggests that it may not be the food itself that confers this risk but rather the way the food is processed or ultra-processed…Further studies are needed to identify specific potential contributing factors among processed foods that might be responsible for the observed associations in our study.”

[Note: This is a fancy way of saying that the detrimental effects of processed foods may be due to more than the fact that they displace healthier foods from the diet. It may also be due to the effect of food additives on the risk of developing IBD.]

What Does This Study Mean For You?

Questioning WomanIBD is a rare disease (0.4% of the population). If you don’t have digestive issues, it would be easy to ignore this study and continue with a diet of highly processed foods.

However, I would remind you that in recent issues of “Health Tips From the Professor”, I have shared recent studies showing that highly processed foods increase your risk of:

And these studies are just the tip of the iceberg. We know that diets rich in whole grains and unprocessed fruits and vegetables decrease the risk of heart attack, stroke, and Alzheimer’s disease. And a diet rich in whole grains, fruits, and vegetables is the antithesis of a processed food diet.

The evidence is overwhelming. Highly processed foods may be convenient and tasty. But if you value your health, they are not your friends.

The Bottom Line 

A recent study looked at the effect of consuming processed foods on the risk of developing inflammatory bowel disease (IBD). The study found:

  • When comparing those eating the most processed food (≥5 servings/day) to those consuming the least (≤1 serving/day), processed food consumption increased the risk of developing IBD by 1.82-fold. This finding was equally true for:
    • Both Crohn’s disease and ulcerative colitis.
    • Adults <50 and adults >50.
    • Every region of the world included in the study.

The investigators concluded, “In this study, higher ultra-processed food intake was associated with a higher risk of IBD.”

They went on to say, “…This study suggests that it may not be the food itself that confers this risk but rather the way the food is processed or ultra-processed…Further studies are needed to identify specific potential contributing factors among processed foods that might be responsible for the observed associations in our study.”

[Note: This is a fancy way of saying that the detrimental effect of processed foods may be due to more than the fact that they displace healthier foods from the diet. It may also be due to the effect of food additives commonly found in processed foods on the risk of developing IBD.]

For more details on the 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?

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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.

Health Tips From The Professor