mortality

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.

Is A Little Alcohol Good For You?

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How Were We Lead Astray?

Author: Dr. Stephen Chaney 

You have probably heard that moderate alcohol consumption is healthier than complete abstinence from alcohol. It is certainly a popular viewpoint.

It is also a scientific paradigm. By that I mean:

  • It is supported by multiple clinical studies.
  • Elaborate metabolic explanations have been proposed to support this paradigm.
  • It is the official position of most medical societies, scientific organizations, and health information sites on the web.
  • It is the recommendation of most health professionals.
  • It has been repeated so often from so many trusted sources that everyone assumes it must be true.

But is it a myth? You may have been surprised if you saw the headlines saying, “Having an alcoholic drink or two per day is not healthier than abstaining.”

Today I will review the study (J Zhao et al, JAMA Network Open, 6(3): e236185, 2023) behind the headlines and tell you what it means for you.

But first, I want to explain to you how the scientific method works. That’s because this study is a perfect example of the scientific method in action.

How Were We Lead Astray?

I have described the scientific method in detail in my books “Slaying The Food Myths” and “Slaying The Supplement Myths”, which you will find here.

Today, I will just give you a brief synopsis of the scientific method.

  • Most scientific studies are designed to disprove existing scientific paradigms. This is such a study.
    • In the scientific world, there is no glory in being the 10th person to prove that a scientific paradigm is correct. The glory comes from being the first person to disprove a scientific paradigm and create a new paradigm in the process.
    • This constant testing of existing paradigms is one of the most important strengths of the scientific method.
  • There is no perfect study. Every study has its flaws.
  • “Confounding variables” are flaws that can be the Achilles Heel of any association study.

Now let me explain the significance of these statements in the context of the current study:

  • All the studies supporting the current paradigm were association studies. Association studies measure the association between a selected variable and an outcome. For these studies, the selected variable was alcohol consumption, and the outcome was increased mortality.
  • Association studies try to statistically correct for other variables known to affect the outcome. For example, diseases like heart disease, diabetes, and cancer increase the risk of premature death. These are known variables that would be corrected for in any well-designed study of alcohol consumption and mortality.
  • “Confounding variables” are unknown variables that also affect the outcome of the study. But since they are unknown, they are not corrected for.

Let me give you a simplistic example of a confounding variable. Let’s say you were doing a study of dietary habits, and you found an association between ice cream consumption and mortality. You might conclude that ice cream consumption is bad for you. It increases your risk of dying.

But then you might remember that ice cream consumption increases during the summer. And then you might reason that people swim more during the summer, and there is a correlation between swimming and drowning deaths.

Swimming could be a confounding variable. To make sure that your initial conclusion that ice cream increases the risk of dying was correct, you would need to correct your data for swimming deaths during the summer and see if you still found a correlation between ice cream consumption and mortality.

Could The Current Paradigm Be Incorrect?

SkepticYou might be thinking, “What does this have to do with studies on the correlation between alcohol consumption and increased mortality?” Let me explain.

The baseline group for these comparisons was the abstainers – the group consuming no alcohol. Previous studies have compared the mortality risk associated with various amounts of alcohol consumption with the mortality risk of the abstainer group. This sounds like a reasonable approach.

But the investigators challenging the current paradigm noted that the “abstainer group” in previous studies included both lifetime abstainers and former drinkers who had become abstainers. They hypothesized that the “former drinkers” group may have become abstainers because of health issues related to excess alcohol consumption.

In short, they hypothesized that the “former drinkers” group was a confounding variable that biased the results of the previous studies. They hypothesized that the “lifetime abstainers” group was a more appropriate baseline group for this kind of study. They then set out to prove their hypothesis.

How Was This Study Done?

clinical studyThe investigators searched the literature and found 107 studies with 4.8 million participants published between 1980 and July 21, 2021, that:

  • Assessed the correlation between alcohol consumption and mortality.
  • Had data that allowed the investigators to separate lifetime abstainers from former drinkers who had become abstainers.

The investigators divided alcohol consumption into low, moderate, high, and very high categories based on the ounces of alcohol consumed per day. Since ounces of alcohol is not an easy measure for most of us, I have converted ounces/day to drinks/day based on the CDC definition of a drink (a 12-ounce beer, 5-ounce glass of wine, or 1.5 ounces of a distilled spirit like gin or vodka). And to make it even simpler, I have rounded to the nearest whole number. With that said, here are the classifications.

  • Low alcohol intake = 1-2 drinks/day.
  • Moderate alcohol intake = 2-3 drinks/day.
  • High alcohol intake = 3-4 drinks/day.
  • Very high alcohol intake = >4 drinks/day.

The risk of death associated with each of these intake levels was compared the risk of death of their preferred baseline group, the “lifetime abstainers”.

Finally, the data were corrected for other variables known to influence the correlation between alcohol consumption and mortality, namely age, sex, heart health, social status, race, diet, exercise, BMI, and smoking status. [These are known confounding variables and had been adjusted for in most previous studies.]

Is A Little Alcohol Good For You?

Red WineWhen the investigators compared the mortality risk of former drinkers who had become abstainers with lifetime abstainers:

  • The former drinkers were 31% more likely to die, and this difference was highly significant.
  • This is consistent with their hypothesis that the “former drinkers” group was a confounding variable that may have biased the conclusions of previous studies.

When they compared the mortality risk of various levels of alcohol consumption with lifetime abstainers instead of all abstainers, they found:

  • The risk of mortality associated with low (1-2 drinks/day) and moderate (2-3 drinks/day) alcohol intake was statistically identical to the risk of mortality for lifetime abstainers.
  • The high alcohol intake group (3-4 drinks/day) was 24% more likely to die than the lifetime abstainers.
  • The very high alcohol intake group (>4 drinks/day) was 39% more likely to die than the lifetime abstainers.

In short, when lifetime abstainers were used as the baseline group, low to moderate alcohol intake did not reduce the risk of dying, as previous studies had suggested. This study suggests the idea that low to moderate alcohol consumption is good for us is not accurate. It is a myth.

Finally, there was a significant gender difference in the effect of alcohol consumption on mortality.

For women:

  • Even moderate alcohol consumption was associated with an increased risk of mortality. Only low alcohol consumption posed no increase in mortality.
  • The increased risk of mortality for women was significantly higher than for men with every level of alcohol consumption.

The authors concluded, “In this…meta-analysis, daily low or moderate alcohol intake was not significantly associated with all-cause mortality risk, while increased risk was evident at higher consumption levels, starting at lower levels for women than for men.”

Of course, this isn’t the end of the story. The scientific method will continue. Old paradigms don’t die easily. Other investigators will challenge the conclusions of this study. Stay tuned. I will give you updates as future studies are published.

What Does This Study Mean For You?

QuestionsIf you like to imbibe, there are two important takeaways from this study.

The bad news is that you can no longer claim that a drink or two a day is healthier than total abstinence from alcohol.

The good news is that this and every study preceding it have found that a drink or two a day is no less healthy than total abstinence. The studies found no increase in mortality associated with low to moderate alcohol intake.

[However, low to moderate alcohol intake may increase your risk of specific diseases. For example, many studies suggest that even low alcohol intake is associated with an increased risk of breast cancer.]

This study also agrees with previous studies that high alcohol intake increases your risk of death, and women are more susceptible to adverse effects of alcohol intake than men.

So, while this study challenges the existing paradigm that low to moderate alcohol intake is beneficial, it does not change the current recommendations on alcohol intake by most health organizations.

For example, the current CDC guidelines are:

  • Adults of legal drinking age should limit alcohol intake to 2 drinks or less per day for men and one drink or less per day for women.
  • Adults who do not drink alcohol should not start. [The current study strengthens this recommendation because it takes away the excuse that low to moderate alcohol consumption is healthier than abstinence.]
  • Drinking less is better than drinking more.

The CDC guidelines also note that the risk of some cancers increases even at very low levels of alcohol consumption.

Finally, the CDC recommends that some people never consume alcohol, including:

  • Women who are pregnant or might become pregnant.
  • Anyone younger than 21.
  • Anyone with medical conditions or medications that interact with alcohol.
  • Anyone recovering from an alcohol use disorder or who has trouble controlling the amount they drink.

The Bottom Line

A recent study is a perfect example of the scientific method in action. Scientists are constantly challenging the existing scientific paradigms, and this is an important strength of the scientific method.

A group of scientists recently published a study challenging the paradigm that low to moderate alcohol intake is healthier than total abstinence from alcohol.

They hypothesized that previous studies supporting this paradigm had a common methodological flaw, corrected for the flaw, and reanalyzed the data from 104 studies with a total of 4.8 million participants.

The revised data showed no health benefit of low to moderate alcohol consumption compared to total abstinence. When you look at the data more closely, the current paradigm may be a myth.

  • This is a major change to the existing paradigm because it removes the justification for low to moderate alcohol consumption.

However, the revised data did not differ from previous studies in the following ways:

  • There is no health risk associated with low to moderate alcohol intake compared to total abstinence.
  • High alcohol intake (>3 drinks/day) is associated with increased mortality.
  • Women are more sensitive to the adverse effects of alcohol than men.

So, this study does not change current guidelines for alcohol consumption.

For more information on this study, what it means for you, and the CDC guidelines on alcohol consumption 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.

 

 

 

 

 

Is It Too Late For Weight Loss Goals?

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What Does This Study Mean For You?

Author: Dr. Stephen Chaney

It’s almost the New Year. And with the New Year comes New Year’s resolutions. Weight loss is the second most popular New Year’s resolution, trailing only exercising more.

But if you are middle-aged and have been overweight most of your adult life, is it too late to lose weight? Has the damage to your health already been done? Has that ship already sailed?

There is good evidence that people who maintain an ideal weight throughout their adult years are healthier and live slightly longer than people who are overweight.

There is also good evidence that weight loss at any age provides short-term improvements to biomarkers of good health such as:

  • lower blood pressure.
  • lower cholesterol levels.
  • better blood sugar control.
  • reduction in chronic inflammation.

But surprisingly there are very few studies to show that weight loss results in long-term health benefits, especially for people who have been overweight through their 40s and 50s. To date there is only a single Chinese study of midlife weight loss, and that study suggested that health benefits were only apparent if the weight loss was maintained for 30 years or more.

The study (TE Strandberg et al, JAMA Network Open, 2025, 8(5); e2511825) I will describe today was designed to fill that gap.

How Was This Study Done?

Clinical StudyThe investigators used data from three large studies that followed healthy individuals in midlife for 10 years or more. None of these studies were designed as weight loss studies, but they measured weight, chronic disease incidence or mortality at multiple points during the study.

The first study was the Whitehall II Study (WHII). This study enrolled 10,308 British civil servants (Whitehall is the district where the British Civil Service is located) between 1985 and 1988 and is still ongoing. The data for this investigation was taken from clinical examinations that occurred around 1991 and 2013.

  • These exams provided information on weight and height, BMI, and risk factors like smoking, high blood pressure, high cholesterol, and insulin resistance and/or high blood sugar (indicative of prediabetes or diabetes).
  • The data set was linked to National Health Service records for diagnosed chronic diseases (type 2 diabetes, heart attack, stroke, cancer, asthma, and chronic obstructive pulmonary disease).

The study I am describing today included 4118 men and women aged 37-42 years (average = 39 years) from the WHII dara set who were free of chronic disease at the time of the 1991 clinical evaluation.

The second study was the Helsinki Businessmen Study (HBS). In this study 3490 White men, mostly businessmen and executives aged 38-45 years (average 42 years) underwent voluntary health checkups starting in 1964. Cardiovascular risk factors were assessed and the men received health education on diet, exercise, and weight control. Between 1974 and 1975 these men were offered a voluntary follow-up health checkup, and 2335 men completed both checkups.

  • In this study, BMI was measured at both health checkups and all-cause mortality data were obtained from the National Health Registry.

The third study was the Finnish Public Sector Study (FPS). In this study 77,111 men and women in public service were enrolled in 2,000. BMI was measured in 4-year intervals and health data were collected from the European Health Records. The data for this investigation used data from 16,696 men and women who were 34-43 (average age = 39) at the first assessment, had data from at least 3 consecutive assessments, and had no diagnosed chronic disease at the first assessment.

  • As with the WHII study, BMI and chronic disease were measured in at least 2 consecutive assessments.

The average follow-up for the three studies was 22.8 years between the first and last assessment.

In all three cases the study participants were divided into 4 groups:

  • Those who remain overweight (defined as a persistent BMI>25).
  • Those who gained weight – they went from a healthy weight to being overweight (defined as BMI<25 to BMI>25).
  • Those who lost weight – they went from overweight to a healthy weight (defined as BMI>25 to BMI<25).
    • The average weight loss was 11.5 pounds or 6.5% of body weight and was remarkably consistent in all 3 studies.
  • Those who remained at a healthy weight (defined as a persistent BMI<25).

In the WHII and FPS studies, weight differences were correlated with the diagnosis of a chronic disease between the first and last assessment.

In the HBS study, weight differences were correlated with all-cause mortality between the first and last assessment.

In all three cases, the data were corrected for major risk factors like smoking, high blood pressure, high cholesterol, and insulin resistance and/or high blood sugar.

In terms of the risk of developing a chronic disease (WHII and FPS studies) or risk of dying (HBS study) the always overweight group was assigned a risk of 1.0 and the other groups were compared to it.

The authors noted that all three studies were performed before surgical and pharmacological interventions were available. And people with pre-existing conditions were excluded from these studies, so disease-related weight loss was unlikely. Thus, the authors felt that the group who lost weight probably did so because of a conscious effort to change their diet and lifestyle, although this was not specifically measured in these studies.

Is It Too Late For A Weight Loss Goal?

If you remember the introduction, this question did not refer to short-term biomarkers of health. Multiple studies have shown that weight loss at any age will improve blood sugar control and lower blood pressure, cholesterol, and inflammation.

This study asked whether weight loss can be shown to have long-term health benefits – namely reduction in the risk of chronic diseases and increase in longevity.

And more specifically, it asked whether weight loss in middle age (the age of participants in these studies ranged from 39 to 42) can be shown to have long-term health benefits – even if they had been overweight for most of their adult life up to that point.

Or as the title of this segment suggested, “Is it too late to set a weight loss goal if you are middle aged.”

The answer from these studies was clear cut:

  • In the WHII study the risk of developing a chronic disease decreased by 48% compared to the always overweight group.
    • And when diabetes was excluded from the analysis the decreased risk was still significant (42%). This is important because diabetes is the most prevalent obesity related disease. The means that weight loss also significantly reduced the risk of the other chronic diseases measured in this study – such as cardiovascular disease and cancer.
  • In the FPS study the risk of developing a chronic disease decreased by 57% compared to the always overweight group.
  • Again, when diabetes was excluded from the analysis the decreased risk was still significant (45%).
  • Finally, in the HBS study, the risk of premature death decreased by 19% compared to the always overweight group.

In each of these studies:

  • The group that gained weight in their middle years did almost as poorly as the always overweight group.

The authors concluded, “Findings from 3 prospective cohort studies support maintaining a healthy weight (BMI<25) throughout life as the best option for overall health. [However] sustained midlife weight loss compared with persistent overweight was associated with a decreased risk of [diabetes and other chronic diseases] and decreased all-cause mortality.”

Simply put, this analysis of three long-term studies shows that weight loss can help you be healthier and live longer in your golden years – even if you waited until you were middle-aged to lose the weight.

What Does This Study Mean For You?

cruise shipAt the beginning of this article I posed the questions: If you are middle-aged and have been overweight most of your adult life, is it too late to set a weight loss goal this January? Has the damage to your health already been done? Has that ship already sailed?

This study shows that the answer to this question is clearly, “No. It’s not too late.” Sustained weight loss can still provide significant long-term benefits.

Three major studies show that sustained weight loss initiated by adults in their forties can reduce the risk of chronic disease by around 50% and reduce the risk of mortality by about 20% twenty years later. The authors of this study said that evidence from one of those studies suggests that the long-term health benefits are still apparent 30 years later.

Of course, these studies represent a single time point – weight loss initiated at age 40.

  • The benefits of sustained weight loss may wane if you delay longer, but we don’t know because those studies have not been done. However, it is likely that sustained weight loss at any age will have significant long-term health benefits.
  • The benefits of sustained weight loss may be even greater if you lose weight at a younger age. Again, we can’t predict how much greater the benefit will be because those studies also haven’t been done yet.
  • However, as the authors of this study said, “Maintaining a healthy weight throughout life is the best option for overall health.” That conclusion is supported by multiple studies.

There are a couple of other important points.

  • These benefits (a 50% reduction in chronic diseases and a 20% increase in longevity) do not require massive weight loss. The subjects in these studies only lost around 11-12 pounds (6.5% of their weight). You have previously heard that as little as 5% weight loss has significant short-term benefits. This study confirms that statement and indicates if the weight loss is sustained, it will significantly improve long-term health outcomes.
  • Weight loss has a bigger effect on quality of life (absence from chronic diseases) than it does on longevity. That is true of every healthy lifestyle improvement that has been studied. I’m sorry to say that losing weight will not help you live as long as Methuselah. But it will help you live your last years in good health.

Of course, losing weight is easy. There are many fad diets that can help you do that. But keeping the weight off is hard. This is where every diet eventually fails. Maintaining weight loss requires lifestyle change. It also requires a change in mindset. It requires that you change how you think about food and how you think about your ability to control what you eat.

This is why I created my online lifestyle change course, “Create Your Personal Health Zone”. If this is the year you have resolved to lose weight and keep it off, check out my course.

What About Weight Loss Surgery and GLP-1 Drugs? 

Weight loss surgery and GLP-1 drugs result in faster and greater weight loss than diet and lifestyle changes alone. For example, clinical trials show that GLP-1 drugs can result in 15-20% body weight loss within the first year. [Subsequent studies suggest that real-life weight loss is often much smaller because of drug discontinuation due to side effects or cost.]

But assuming the 15-20% number, the question becomes whether these interventions have the same or greater benefits than the 6.5% body weight loss due to diet and lifestyle change seen in these studies.

The short answer is that we don’t know because we don’t have any long-term studies of these interventions. However, the authors of this study were skeptical. They said, “It remains uncertain whether the long-term benefits observed in our study extend to these interventions, where greater weight loss may be accompanied by a concurrent and potentially significant loss of lean body mass, which could pose challenges over time.”

I have discussed the importance of muscle mass for health and longevity in a previous issue  of “Health Tips From the Professor”. This article shows why the accelerated loss of muscle mass seen with GLP-1 drugs is so concerning.

The Bottom Line 

The time to set your New Year’s goals is just a few weeks away. If you are middle-aged and have been overweight most of your adult life, is it too late to set a weight loss goal this January? Has the damage to your health already been done? Has that ship already sailed?

A recent study examined that question. The study used data from three earlier studies on the long-term effects of sustained weight loss (20 years or more). These studies show that sustained weight loss initiated by adults in their 40s reduces the risk of:

  • Chronic disease by around 50%.
  • Mortality by about 20%.
  • Data from one of those studies suggests that the long-term health benefits were still apparent 30 years later.

For more information on this study, what it means for you, and where weight loss surgery and GLP-1 drugs fit into the picture, 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 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.

The Alcohol Myth

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How Were We Led Astray?

Author: Dr. Stephen Chaney 

You have probably heard that moderate alcohol consumption is healthier than complete abstinence from alcohol. It is certainly a popular viewpoint.

It is also a scientific paradigm. By that I mean:

  • It is supported by multiple clinical studies.
  • Elaborate metabolic explanations have been proposed to support this paradigm.
  • It is the official position of most medical societies, scientific organizations, and health information sites on the web.
  • It is the recommendation of most health professionals.
  • It has been repeated so often from so many trusted sources that everyone assumes it must be true.

But is it a myth? You may have been surprised when you saw recent headlines saying, “Having an alcoholic drink or two per day is not healthier than abstaining.”

Today I will review the study (J Zhao et al, JAMA Network Open, 6(3): e236185, 2023) behind the headlines and tell you what it means for you.

But first, I want to explain to you how the scientific method works. That’s because this study is a perfect example of the scientific method in action.

How Were We Led Astray?

I have described the scientific method in detail in my books “Slaying The Food Myths” and “Slaying The Supplement Myths”, which you will find here.

Today, I will just give you a brief synopsis of the scientific method.

1) Most scientific studies are designed to disprove existing scientific paradigms. This is such a study.

  • In the scientific world, there is no glory in being the 10th person to prove that a scientific paradigm is correct. The glory comes from being the first person to disprove a scientific paradigm and create a new paradigm in the process.
  • This constant testing of existing paradigms is one of the most important strengths of the scientific method.

2) There is no perfect study. Every study has its flaws.

  • “Confounding variables” are flaws that can be the Achilles Heel of any association study.

Now let me explain the significance of these statements in the context of the current study:

  • All the studies supporting the current paradigm were association studies. Association studies measure the association between a selected variable and an outcome. For these studies, the selected variable was alcohol consumption, and the outcome was increased mortality.
    • Association studies try to statistically correct for other variables known to affect the outcome. For example, diseases like heart disease, diabetes, and cancer increase the risk of premature death. These are known variables that would be corrected for in any well-designed study of alcohol consumption and mortality.
    • “Confounding variables” are unknown variables that also affect the outcome of the study. But since they are unknown, they are not corrected for.

Let me give you a simplistic example of a confounding variable. Let’s say you were doing a study of dietary habits, and you found an association between ice cream consumption and mortality. You might conclude that ice cream consumption is bad for you. It increases your risk of dying.

But then you might remember that ice cream consumption increases during the summer. And then you might reason that people swim more during the summer, and there is a correlation between swimming and drowning deaths.

Swimming could be a confounding variable. To make sure that your initial conclusion that ice cream increases the risk of dying was correct, you would need to correct your data for swimming deaths during the summer and see if you still found a correlation between ice cream consumption and mortality.

Could The Current Paradigm Be Incorrect?

SkepticYou might be thinking, “What does this have to do with studies on the correlation between alcohol consumption and increased mortality?” Let me explain.

The baseline group for these comparisons was the abstainers – the group consuming no alcohol. Previous studies have compared the mortality risk associated with various amounts of alcohol consumption with the mortality risk of the abstainer group. This sounds like a reasonable approach.

But the investigators challenging the current paradigm noted that the “abstainer group” in previous studies included both lifetime abstainers and former drinkers who had become abstainers. They hypothesized that the “former drinkers” group may have become abstainers because of health issues related to excess alcohol consumption.

In short, they hypothesized that the “former drinkers” group was a confounding variable that biased the results of the previous studies. They hypothesized that the “lifetime abstainers” group was a more appropriate baseline group for this kind of study. They then set out to prove their hypothesis.

How Was This Study Done?

clinical studyThe investigators searched the literature and found 107 studies with 4.8 million participants published between 1980 and July 21, 2021, that:

  • Assessed the correlation between alcohol consumption and mortality.
  • Had data that allowed the investigators to separate lifetime abstainers from former drinkers who had become abstainers.

The investigators divided alcohol consumption into low, moderate, high, and very high categories based on the ounces of alcohol consumed per day. Since ounces of alcohol is not an easy measure for most of us, I have converted ounces/day to drinks/day based on the CDC definition of a drink (a 12-ounce beer, 5-ounce glass of wine, or 1.5 ounces of a distilled spirit like gin or vodka). And to make it even simpler, I have rounded to the nearest whole number. With that said, here are the classifications.

  • Low alcohol intake = 1-2 drinks/day.
  • Moderate alcohol intake = 2-3 drinks/day.
  • High alcohol intake = 3-4 drinks/day.
  • Very high alcohol intake = >4 drinks/day.

The risk of death associated with each of these intake levels was compared the risk of death of their preferred baseline group, the “lifetime abstainers”.

Finally, the data were corrected for other variables known to influence the correlation between alcohol consumption and mortality, namely age, sex, heart health, social status, race, diet, exercise, BMI, and smoking status. [These are known confounding variables and had been adjusted for in most previous studies.]

The Alcohol Myth

Red WineWhen the investigators compared the mortality risk of former drinkers who had become abstainers with lifetime abstainers:

  • The former drinkers were 31% more likely to die, and this difference was highly significant.
  • This is consistent with their hypothesis that the “former drinkers” group was a confounding variable that may have biased the conclusions of previous studies.

When they compared the mortality risk of various levels of alcohol consumption with lifetime abstainers instead of all abstainers, they found:

  • The risk of mortality associated with low (1-2 drinks/day) and moderate (2-3 drinks/day) alcohol intake was statistically identical to the risk of mortality for lifetime abstainers.
  • The high alcohol intake group (3-4 drinks/day) was 24% more likely to die than the lifetime abstainers.
  • The very high alcohol intake group (>4 drinks/day) was 39% more likely to die than the lifetime abstainers.

In short, when lifetime abstainers were used as the baseline group, low to moderate alcohol intake did not reduce the risk of dying, as previous studies had suggested. This study suggests the idea that low to moderate alcohol consumption is good for us may not be accurate. It may be a myth.

Finally, there was a significant gender difference in the effect of alcohol consumption on mortality.

For women:

  • Even moderate alcohol consumption was associated with an increased risk of mortality. Only low alcohol consumption posed no increase in mortality.
  • The increased risk of mortality for women was significantly higher than for men with every level of alcohol consumption.

The authors concluded, “In this…meta-analysis, daily low or moderate alcohol intake was not significantly associated with all-cause mortality risk, while increased risk was evident at higher consumption levels, starting at lower levels for women than for men.”

Of course, this isn’t the end of the story. The scientific method will continue. Old paradigms don’t die easily. Other investigators will challenge the conclusions of this study. Stay tuned. I will give you updates as future studies are published.

What Does This Study Mean For You?

QuestionsIf you like to imbibe, there are two important takeaways from this study.

The bad news is that you can no longer claim that a drink or two a day is healthier than total abstinence from alcohol.

The good news is that this and every study preceding it have found that a drink or two a day is no less healthy than total abstinence. The studies found no increase in mortality associated with low to moderate alcohol intake.

[However, low to moderate alcohol intake may increase your risk of specific diseases. For example, many studies suggest that even low alcohol intake is associated with an increased risk of breast cancer.]

This study also agrees with previous studies that high alcohol intake increases your risk of death, and women are more susceptible to adverse effects of alcohol intake than men.

So, while this study challenges the existing paradigm that low to moderate alcohol intake is beneficial, it does not change the current recommendations on alcohol intake by most health organizations.

For example, the current CDC guidelines are:

  • Adults of legal drinking age should limit alcohol intake to 2 drinks or less per day for men and one drink or less per day for women.
  • Adults who do not drink alcohol should not start. [The current study strengthens this recommendation because it takes away the excuse that low to moderate alcohol consumption is healthier than abstinence.]
  • Drinking less is better than drinking more.

The CDC guidelines also note that the risk of some cancers increases even at very low levels of alcohol consumption.

Finally, the CDC recommends that some people never consume alcohol, including:

  • Women who are pregnant or might become pregnant.
  • Anyone younger than 21.
  • Anyone with medical conditions or medications that interact with alcohol.
  • Anyone recovering from an alcohol use disorder or who has trouble controlling the amount they drink.

The Bottom Line 

A recent study is a perfect example of the scientific method in action. Scientists are constantly challenging the existing scientific paradigms, and this is an important strength of the scientific method.

A group of scientists recently published a study challenging the paradigm that low to moderate alcohol intake is healthier than total abstinence from alcohol.

They hypothesized that previous studies supporting this paradigm had a common methodological flaw, corrected for the flaw, and reanalyzed the data from 104 studies with a total of 4.8 million participants.

The revised data showed no health benefit of low to moderate alcohol consumption compared to total abstinence. When you look at the data more closely, the current paradigm may be a myth.

  • This is a major change to the existing paradigm because it removes the justification for low to moderate alcohol consumption.

However, the revised data did not differ from previous studies in the following ways:

  • There is no health risk associated with low to moderate alcohol intake compared to total abstinence.
  • High alcohol intake (>3 drinks/day) is associated with increased mortality.
  • Women are more sensitive to the adverse effects of alcohol than men.

So, this study does not change current guidelines for alcohol consumption.

For more information on this study, what it means for you, and the CDC guidelines on alcohol consumption 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 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.

Are Low Carb Diets Healthier?

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The “Goldilocks Effect”

Author: Dr. Stephen Chaney

Goldilocks EffectThe low-carb wars rage on. Low-carb enthusiasts claim that low-carb diets are healthy. Many health experts warn about the dangers of low-carb diets. Several studies have reported that low-carb diets increase risk of mortality (shorten lifespan).

However, two recent studies have come to the opposite conclusion. Those studies reported that high carbohydrate intake increased mortality, and low carbohydrate intake was associated with the lowest mortality.

One of those studies, called the Prospective Urban Rural Epidemiology (PURE) study was published a few years ago. It included data from 135,335 participants from 18 countries across 5 continents. That’s a very large study, and normally we expect very large studies to be accurate. The results from the PURE study had low-carb enthusiasts doing a victory lap and claiming it was time to rewrite nutritional guidelines to favor low-carb diets.

Whenever controversies like this arise, reputable scientists are motivated to take another look at the question. They understand that all studies have their weaknesses and biases. So, they look at previous studies very carefully and try to design a study that eliminates the weaknesses and biases of those studies. Their goal is to design a stronger study that reconciles the differences between the previous studies.

A third study published a year later (SB Seidelmann et al, The Lancet, doi.org/10.1016/S2468-2667(18)30135-X was such a study. This study resolved the conflicting data and finally answered the question: “How much carbohydrate should we be eating if we desire a long and healthy life?” The answer is “Enough”.

I call this “The Goldilocks Effect”. You may remember “Goldilocks And The Three Bears”. One bed was too hard. One bed was too soft. But one bed was “just right”. One bowl of porridge was too hot. One was two cold. But one was “just right”. According to this study, the same is true for carbohydrate intake. High carbohydrate intake is unhealthy. Low carbohydrate intake is unhealthy. But moderate carbohydrate intake is “just right”.

How Was The Study Done?

clinical studyThis study was performed in two parts. This first part drew on data from the Atherosclerosis Risk in Communities (ARIC) study. That study enrolled 15,428 men and women, aged 45-64, from four US communities between 1987 and 1989. This group was followed for an average of 25 years, during which time 6283 people died. Carbohydrate intake was calculated based on food frequency questionnaires administered when participants enrolled in the study and again 6 years later. The study evaluated the association between carbohydrate intake and mortality.

The second part was a meta-analysis that combined the data from the ARIC study with all major clinical studies since 2007 that measured carbohydrate intake and mortality and lasted 5 years or more. The total number of participants included in this meta-analysis was 432,179, and it included data from previous studies that claimed low-carbohydrate intake was associated with decreased mortality.

Are Low Carb Diets Healthier?

GravestoneThe results from the ARIC study were:

  • The relationship between mortality and carbohydrate intake was a U-shaped curve.
    • The lowest risk of death was observed with a moderate carbohydrate intake (50-55%). This is the intake recommended by current nutrition guidelines.
    • The highest risk of death was observed with a low carbohydrate intake (<40%).
    • The risk of death also increased with very high carbohydrate intake (>70%).
  • When the investigators used the mortality data to estimate life expectancy, they predicted a 50-year old participant would have a projected life expectancy of:
    • 33.1 years if they had a moderate intake of carbohydrates.
    • 4 years less if they had a low carbohydrate intake.
    • 1.1 year less if they had a very high carbohydrate intake.
  • The risk associated with low carbohydrate intake was affected by what the carbohydrate was replaced with.
    • When carbohydrates were replaced with animal protein and animal fat there was an increased risk of mortality on a low-carb diet. The animal-based low-carb diet contained more beef, pork, lamb, chicken, and fish. It was also higher in saturated fat.Beans and Nuts
    • When carbohydrates were replaced with plant protein and plant fats, there was a decreased risk of mortality on a low-carb diet. The plant-based low-carb diet contained more nuts, peanut butter, dark or whole grain breads, chocolate, and white bread. It was also higher in polyunsaturated fats.
  • The effect of carbohydrate intake on mortality was virtually the same for all-cause mortality, cardiovascular mortality, and non-cardiovascular mortality.
  • There was no significant effect of carbohydrate intake on long-term weight gain (another myth busted).

The results from the dueling meta-analyses were actually very similar. When the data from all studies were combined:

  • Both very low carbohydrate diets and very high carbohydrate diets were associated with increased mortality.
  • Meat-based low-carb diets increased mortality, and plant-based low-carb diets decreased mortality.
  • Once again, the results were the same for total mortality, cardiovascular mortality, and non-cardiovascular mortality.

The authors concluded: “Our findings suggest a negative long-term association between life-expectancy and both low carbohydrate and high carbohydrate diets…These data also provide further evidence that animal-based low carbohydrate diets should be discouraged. Alternatively, when restricting carbohydrate intake, replacement of carbohydrates with predominantly plant-based fats and proteins could be considered as a long-term approach to healthy aging.”

Simply put, that means if a low carb diet works best for you, it is healthier to replace the carbs with plant-based fats and protein rather than animal-based fats and protein.

The “Goldilocks Effect”

low carb dietThis study also resolved the discrepancies between previous studies. The authors pointed out that the average carbohydrate intake is very different in Europe and the US than in Asian countries and low-income countries.

In the US and Europe mean carbohydrate intake is about 50% of calories and it ranges from 25% to 70% of calories. With that range of carbohydrate intake, it is possible to observe the increase in mortality associated with both very low and very high carbohydrate intakes.

The US and European countries are affluent, which means that low-carb enthusiasts can afford diets high in animal protein.

White rice is a staple in Asian countries, and protein is a garnish rather than a main course. Consequently, overall carbohydrate intake is greater in Asian countries and very few Asians eat a truly low carbohydrate diet. High protein foods tend to be more expensive than high carbohydrate foods. Thus, very few people in developing countries can afford to follow a very low carbohydrate diet, and overall carbohydrate intake also tends to be higher.

Therefore, in Asian and developing countries the average carbohydrate intake is greater (~61%) than in the US and Europe, and the range of carbohydrate intake is from 45% to 80% of calories. With that range of intake, it is only possible to see the increase in mortality associated with very high carbohydrate intake.

Both the studies that low-carb enthusiasts quote to support their claim that low-carb diets are healthy relied heavily on data from Asian and developing countries.ARIC Study

In fact, when the authors of the current study overlaid the data from the PURE study with their ARIC data, there was an almost perfect fit. The only difference was that their ARIC data covered both low and high carbohydrate intake while the PURE study touted by low-carb enthusiasts only covered moderate to high carbohydrate intake.

[I have given you my rendition of the graph on the right. If you would like to see the data yourself, look at the paper.]

Basically, low-carb advocates are telling you that diets with carbohydrate intakes of 30% or less are healthy based on studies that did not include carbohydrate intakes below 40%. That is misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets.

What Does This Study Mean For You?

QuestionsThere are several important take-home lessons from this study:

  • All major studies agree that very high carbohydrate intake is unhealthy. In part, that reflects the fact that diets with high carbohydrate intake are likely to be high in sodas and sugary junk foods. It may also reflect the fact that diets which are high in carbohydrate are often low in plant protein or healthy fats or both.
  • All studies that cover the full range of carbohydrate intake agree that very low carbohydrate intake is also unhealthy. It shortens the life expectancy of a 50-year-old by about 4 years.
  • The studies quoted by low carb enthusiasts to support their claim that low-carb diets are healthy don’t include carbohydrate intakes below 40%. That means their claims are misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets.
  • Meat-based low-carb diets decrease life expectancy while plant-based low carb diets increase life expectancy. This is consistent with previous studies. For more details on those studies, see my article, “Are Any Low-Carb Diets Healthy?”, in “Health Tips From The Professor” or my book, “Slaying The Food Myths”.

The health risks of meat-based low-carb diets may be due to the saturated fat content or the heavy reliance on red meat. However, the risks are just as likely to be due to the foods these diets leave out – typically fruits, whole grains, legumes, and some vegetables.

Proponents of low-carb diets assume that you can make up for the missing nutrients by just taking multivitamins. However, each food group also provides a unique combination of phytonutrients and fibers. The fibers, in turn, influence your microbiome. Simply put, whenever you leave out whole food groups, you put your health at risk.

The Bottom Line

The low-carb wars are raging. Several studies have reported that low-carb diets increase risk of mortality (shorten lifespan). However, two studies published a few years ago have come to the opposite conclusion. Those studies have low-carb enthusiasts doing a victory lap and claiming it is time to rewrite nutritional guidelines to favor low-carb diets.

However, a study published a year later resolves the conflicting data and finally answers the question: “How much carbohydrate should we be eating if we desire a long and healthy life?” The answer is “Enough”.

I call this “The Goldilocks Effect”. According to this study, high carbohydrate intake is unhealthy. Low carbohydrate intake is unhealthy. But, moderate carbohydrate intake is “just right”.

Specifically, this study reported:

  1. Moderate carbohydrate intake (50-55%) is healthiest. This is also the carbohydrate intake recommended by current nutritional guidelines.

2) All major studies agree that very high carbohydrate intake (60-70%) is unhealthy. It shortens life expectancy of a 50-year old by about a year.

3) All studies that cover the full range of carbohydrate intake agree that low carbohydrate intake (<40%) is also unhealthy. It shortens life expectancy of a 50-year old by about 4 years.

4) The studies quoted by low carb enthusiasts to support their claim that low-carb diets are healthy don’t include carbohydrate intakes below 40%. That means their claims are misleading. The studies they quote are incapable of detecting the risks of low carbohydrate diets.

5) Meat-based low-carb diets decrease life expectancy while plant-based low carb diets increase life expectancy. This is consistent with the results of previous studies.

The authors concluded: “Our findings suggest a negative long-term association between life-expectancy and both low carbohydrate and high carbohydrate diets…These data also provide further evidence that animal-based low carbohydrate diets should be discouraged. Alternatively, when restricting carbohydrate intake, replacement of carbohydrates with predominantly plant-based fats and proteins could be considered as a long-term approach to healthy aging.”

Simply put, that means if a low carb diet works best for you, it is healthier to replace the carbs with plant-based fats and protein rather than animal-based fats and protein.

For more details, read the article above.

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

Walking Your Way To Health

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How Much Should You Walk? 

Author: Dr. Stephen Chaney 

Overweight People ExercisingThe new year is almost here. If you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

The problem is these are all expensive options. And a good portion of that money is wasted. To put it into perspective, let’s look at some statistics

  • Around 6 million Americans buy gym memberships every January.
  • 67% of those memberships are never used.
  • For those memberships used in January, another 50% are not in use 6 months later.
  • Americans spend about 1.6 billion dollars on unused gym memberships every year.
  • And that doesn’t include those gym memberships that are only occasionally used.

If you want to get fit and healthy in the new year, perhaps you should consider a less expensive option – like walking. Your only investments are a good pair of walking shoes and a device that keeps track of the number of steps you take (eg, Fitbit, smart watch, or smart phone).

You still may give up on your New Year’s goal of getting fitter at some point. But you won’t have wasted so much money.

Of course, you probably have some questions about the benefits of walking, such as:

  1. Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022; J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) have answered all three questions.

How Were These Studies Done?

clinical studyThe first study (B del Pozo-Cruz et al, JAMA Internal Medicine, 182: 1139-1148, 2022) followed 78,500 participants (average age 61, 55% female, 97% white) enrolled in the UK Biobank study for an average of 7 years.

At the time of enrollment, each participant was given an accelerometer (a device that measures the number and frequency of steps) to wear on their dominant wrist for 24 hours/day for 7 days. The investigators used the accelerometer data to categorize several types of physical activity.

  • Daily step counts (the average number of steps per day for 7 days). These step counts were further subdivided into two categories:
  • Incidental steps (It was assumed that ˂40 steps/min represented steps taken that were incidental to normal daily activities).
  • Purposeful steps (It was assumed that ≥40 steps/min represented steps taken as part of planned exercise).
  • Stepping intensity (the highest frequency of steps/min averaged over 30 min intervals for all 7 days).

At the end of the study, each of these variables was correlated with the risk of premature deaths due to all causes, cancer, and heart disease.

The second study (J del Pozo-Cruz et al, Diabetes Care, 45: 2156-2158, 2022) was similar except that it:

  • Used data from 1687 adults (average age = 55, 56% male, with diabetes or prediabetes when the study began) in the 2005-2006 National Health and Nutrition Examination Survey in the US.
  • Followed participants for 9 years instead of 7.
  • Only measured total steps/day
  • Correlated total steps/day with premature death for participants who already had prediabetes or diabetes when they entered the study.

Walking Your Way To Health

Study 1 looked at the effect of walking on health outcomes in multiple ways.

woman walking dog#1: Increase in number of steps/day:

  • On average study participants took an average of 7200 steps per day, but this ranged from a low of 3,200 steps/day to a high of 12,200 steps/day.
  • Each increase of 2,000 steps/day was associated with a:
    • 8% decrease in all-cause mortality.
    • 11% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.
  • Overall, increasing from 3,200 steps/day to 10,000 steps/day decreased all-cause, cancer, and heart disease mortality by around 36%.
  • There was no minimum threshold to this beneficial effect of walking on the risk of premature death.
  • The benefits of walking appeared to plateau at 10,000 steps/day.

#2: Increase in number of incidental steps/day (steps taken that are incidental to normal daily activities):

  • On average study participants took 3240 incidental steps/day, but this ranged from a low of 2,100 steps/day to a high of 4,400 steps/day.
  • Each 10% increase in incremental steps/day was associated with a:
    • 6% decrease in all-cause mortality.
    • 6% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#3: Increase in number of purposeful steps/day (steps taken as part of planned exercise):

  • On average study participants took 4,600 purposeful steps/day, but this ranged from a low of 1,600 steps/day to a high of 8,600 steps/day.
  • Each 10% increase in purposeful steps/day was associated with a:
    • 7% decrease in all-cause mortality.
    • 8% decrease in cancer mortality.
    • 10% decrease in heart disease mortality.

#4: Increase in speed of walking or cadence. The measurement they used was “peak-30 cadence” – the Walking Fasthighest average steps/min during a 30-minute interval within a day:

  • On average study participants had a “peak-30 cadence” of 76 steps/min, but this ranged from a low of 47 steps/min to a high of 109 steps/min.
  • Each 10% increase in “peak-30 cadence” was associated with a:
    • 8% decrease in all-cause mortality.
    • 9% decrease in cancer mortality.
    • 14% decrease in heart disease mortality.
  • The benefits of walking rapidly (increase in “peak-30 cadence”) were in addition to the benefits seen by increasing the number of steps per day.
  • Overall, increasing from a “peak-30 cadence” of 47 steps/min to 109 steps/min decreased all-cause, cancer, and heart disease mortality by an additional 34%.
  • There was no minimum threshold to this beneficial effect of increasing “peak-30 cadence” (the speed of walking) on the risk of premature death.
  • The benefits of increasing “peak-30 cadence” appeared to plateau at 100 steps/min.

#5 Effect of walking on the prevention of heart disease and cancer: The investigators measured this by strong heartlooking at the effect of walking on the “incidence” of heart disease and cancer (defined as new diagnoses of heart disease and cancer) during the study. They found.

  • Each 2,000-step increase in the total number of steps/day decreased the risk of developing heart disease and cancer by 4% during this 7-year study.
  • Each 10% increase in the number of purposeful steps/day decreased the risk of developing heart disease and cancer by 4% during this study.
  • Each 10% increase in “peak-30 cadence” decreased the risk of developing heart disease and cancer by 7% during this study.

The authors concluded, “The findings of this population-based…study of 78,500 individuals suggest that up to 10,000 steps/day may be associated with a lower risk of mortality and cancer and CVD incidence. Steps performed at a higher cadence may be associated with additional risk reduction, particularly for incident disease.”

Study 2 extended these findings to diabetes. They started with participants that had either prediabetes or diabetesdiabetes and followed them for 9 years. They found that:

  • Study participants with prediabetes ranged from a low of 3,800 steps/day to a high of 10,700 steps/day.
    • Prediabetic participants walking 10,700 steps/day were 25% less likely to die during the study than participants walking only 3,800 steps/day.
  • Study participants with diabetes ranged from a low of 2,500 steps/day to a high of 10,200 steps/day.
    • Diabetic participants walking 10,200 steps/day were also 25% less likely to die during the study than participants walking only 2,500 steps/day.
  • Even small increases in the number of steps per day decreased the risk of premature death for both prediabetic and diabetic participants.
  • Once again, 10,000 steps/day appeared to be the optimal dose to lower the risk of premature death for both diabetic and prediabetic patients.

The authors of this study concluded, “Accumulating more steps/day up to ~10,000 steps/day may lower the risk of all-cause mortality of adults with prediabetes and diabetes.”

How Much Should You Walk?

Walking CoupleThat was a lot of information. You are probably wondering what it means for you. Let’s start with the big picture:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.

In other words, simply walking more and walking faster can have a significant on your health. I am not recommending walking as your only form of exercise. I’m just saying not to consider it inferior to other forms of exercise.

  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.

In other words, you don’t need to speed walk 10,000 steps/day to reap a benefit from walking. Even small increases are beneficial. That’s good news for those of you who may not be able to speed walk long distances. It also means that if you are a couch potato, you don’t need to attempt 10,000 steps at high speed from day 1. You can work up to it gradually.

  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).

That’s good news for those of you who may not have time for long walks. It also means that advice like “park your car at the far end of the parking lot and walk” or “take the stairs rather than the elevator” can have a meaningful impact on your health.

  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

That means once you get to those levels, it’s time to consider adding other kinds of exercise to your regimen. More and faster walking may offer little additional benefit.

Finally, in the words of the authors, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

The Bottom Line 

The new year is almost here. If you are like millions of Americans, you may already be making plans to join a gym, get a personal trainer, or join a spin class.

If you want to get fit and healthy in the new year, perhaps you should also consider a less expensive option – like walking.

Of course, you probably have some questions about the benefits of walking, such as:

1) Is walking enough to significantly improve my fitness and health?

2) How far (how many steps) should I walk?

3) How fast should I walk?

Fortunately, two recent studies have answered all three questions. They found:

  • Going from couch potato to 10,000 steps per day may reduce your risk of premature death due to all causes, cancer, and heart disease by 36% (24% if you are already prediabetic or diabetic).
  • Increasing the speed with which you walk from 47 steps/min to 109 steps/min sustained for 30 minutes may reduce your risk of premature death by an additional 34%.
  • There is no lower limit to the benefits of walking. Even small increases in the number of steps/day you take and the speed with which you walk may have a beneficial effect on your health.
  • Incidental walking (walking that is incidental to your daily activities) is almost as beneficial as purposeful walking (walking as part of a planned exercise).
  • The benefits of walking appear to max out at around 10,000 steps per day and a cadence of 100 steps/min sustained for 30 minutes.

In the words of the authors of these studies, “This information could be used to motivate the least active individuals to increase their steps and the more-active individuals to reach the 10,000-step target.”

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.

 

Should I Avoid Whole Grains?

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Will Whole Grains Kill Me?

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

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

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

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

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

How Was The Study Done?

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

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

Will Whole Grains Kill Me?

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

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

That is not what this study showed.

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

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

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

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

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

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

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

Should I Avoid Whole Grains?

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

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

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

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

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

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

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

The Bottom Line

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

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

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

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

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

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

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

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

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

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

For more details read the article above.

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

Health Tips From The Professor