omega-3s Archives - Health Tips From The Professor

Which Supplements Are Good For Your Heart?

February 7, 2023 by Dr. Steve Chaney

How Should You Interpret This Study?

Author: Dr. Stephen Chaney

February is Heart Health month. So, it is fitting that we ask, “What is the status of heart health in this country?” The American Heart Association just published an update of heart health statistics through 2019 (CW Tsao et al, Circulation, 145: e153-e639, 2022). And the statistics aren’t encouraging. [Note: The American Heart Association only reported statistics through 2019 because the COVID-19 pandemic significantly skewed the statistics in 2020 and 2021].

The Good News is that between 2009 and 2019:

All heart disease deaths have decreased by 25%.
Heart attack deaths have decreased by 6.6%.
Stroke deaths have decreased by 6%.

The Bad News is that:

Heart disease is still the leading cause of death in this country.
Someone dies from a heart attack every 40 seconds.
Someone dies from a stroke every 3 minutes.

Diet, exercise, and weight control play a major role in reducing the risk of heart disease. Best of all, they have no side effects. They represent a risk-free approach that each of us can control.

But is there something else? Could supplements play a role? Are supplements hype or hope for a healthy heart?

All the Dr. Strangeloves in the nutrition space have their favorite heart health supplements. They claim their supplements will single-handedly abolish heart disease (and help you leap tall buildings in a single bound).

On the other hand, many doctors will tell you these supplements are a waste of money. They don’t work. They just drain your wallet.

It’s so confusing. Who should you believe? Fortunately, a recent study (P An et al, Journal of the American College of Cardiology, 80: 2269-2285, 2022) has separated the hype from the hope and tells us which “heart-healthy” supplements work, and which don’t.

How Was This Study Done?

This was a major clinical study carried out by researchers from the China Agricultural University and Brown University in the US. It was a meta-analysis, which means it combined the data from many published clinical trials.

The investigators searched three major databases of clinical trials to identify:

884 randomized, placebo-controlled clinical studies…

Of 27 types of micronutrients…

With a total of 883,627 patients…

Looking at the effectiveness of micronutrient supplementation lasting an average of 3 years on either…

- Cardiovascular risk factors like blood pressure, total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides…or…

- Cardiovascular outcomes such as coronary heart disease (CHD), heart attacks, strokes, and deaths due to cardiovascular disease (CVD) and all causes.

[Note: Coronary heart disease (CHD) refers to build up of plaque in the coronary arteries (the arteries leading to the heart). It is often referred to as heart disease and can lead to heart attacks (myocardial infarction). Cardiovascular disease (CVD) is a more inclusive term that includes coronary heart disease, stroke, congenital heart defects, and peripheral artery disease.]

The investigators also included an analysis of the quality of the data in each of the clinical studies and rated the evidence of each of their findings as high quality, moderate quality, or low quality.

Which Supplements Are Good For Your Heart?

The top 3 heart-healthy supplements in this study were:

Omega-3 Fatty Acids:

Increased HDL cholesterol and decreased triglycerides, both favorable risk factors for heart health.
Deceased risk of heart attacks by 15%, all CHD events by 14%, and CVD deaths by 7% (see definitions of CHD and CVD above).
The median dose of omega-3 fatty acids in these studies was 1.8 g/day.
The evidence was moderate quality for all these findings.

Folic Acid:

Decreased LDL cholesterol (moderate quality evidence) and decreased blood pressure and total cholesterol (low quality evidence).
Decreased stroke risk by 16% (moderate quality evidence).

Coenzyme Q10:

Decreased triglycerides (high quality evidence) and reduced blood pressure (low quality evidence).
Decreased the risk of all-cause mortality by 32% (moderate quality evidence).
These studies were performed with patients diagnosed with heart failure. Coenzyme Q10 is often recommended for these patients, so the studies were likely performed to test the efficacy of this treatment.

There were three micronutrients (vitamin C, vitamin E, and vitamin D) that did not appear to affect heart disease outcomes.

Finally, as reported in previous studies, β-carotene increased the risk of stroke, CVD mortality, and all-cause mortality.

In terms of the question I asked at the beginning of this article, this study concluded that:

Omega-3, folic acid, and coenzyme Q10 supplements represent hope for a healthy heart.
Vitamin C, vitamin E, and vitamin D supplements represent hype for a healthy heart.
β-carotene supplements represent danger for a healthy heart.

But these conclusions just scratch the surface. To put them into perspective we need to dig a bit deeper.

How Should You Interpret This Study?

In evaluating the significance of these findings there are two things to keep in mind.

#1: This study is a meta-analysis and meta-analyses have both strengths and weaknesses.

The strength of meta-analyses is that by combining multiple clinical studies they can end up with a database containing 100s of thousands of subjects. This allows them to do two things:

It allows the meta-analysis to detect statistically significant effects that might be too small to detect in an individual study.
It allows the meta-analysis to detect the average effect of all the clinical studies it includes.

The weakness of meta-analyses is that the design of individual studies included in the analysis varies greatly. The individual studies vary in things like dose, duration, type of subjects included in the study, and much more.

This is why this study rated most of their conclusions as backed by moderate- or low-quality evidence. [Note: The fact that the authors evaluated the quality of evidence is a strength of this study. Most meta-analyses just report their conclusions without telling you how strong the evidence behind those conclusions is.]

#2: Most clinical studies of supplements (including those included in this meta-analysis) have two significant weaknesses.

Most studies do not measure the nutritional status of their subjects prior to adding the supplement. If their nutritional status for a particular nutrient was already optimal, there is no reason to expect more of that nutrient to provide any benefit.
Most studies measure the effect of a supplement on a cross-section of the population without asking who would be most likely to benefit.

You would almost never design a clinical study that way if you were evaluating the effectiveness of a potential drug. So, why would you design clinical studies of supplements that way?

With these considerations in mind, let me provide some perspective on the conclusions of this study.

Coenzyme Q10:

This meta-analysis found that coenzyme Q10 significantly reduced all-cause mortality in patients with heart failure. This is consistent with multiple clinical studies and a recent Cochrane Collaboration review.

Does coenzyme Q10 have any heart health benefits for people without congestive heart failure? There is no direct evidence that it does, but let me offer an analogy with statin drugs.

Statin drugs are very effective at reducing heart attacks in high-risk patients. But they have no detectable effect on heart attacks in low-risk patients. However, this has not stopped the medical profession from recommending statins for millions of low-risk patients. The rationale is that if they are so clearly beneficial in high-risk patients, they are “probably” beneficial in low-risk patients.

I would argue a similar rationale should apply to supplements like coenzyme Q10.

Omega-3s:

This study found that omega-3 reduced both heart attacks and the risk of dying from heart disease. Most previous meta-analyses of omega-3s and heart disease have come to the same conclusion. However, some meta-analyses have failed to find any heart health benefits of omega-3s. Unfortunately, this has allowed both proponents and opponents of omega-3 use for heart health to quote studies supporting their viewpoint.

However, there is one meta-analysis that stands out from all the others. A group of 17 scientists from across the globe collaborated in developing a “best practices” experimental design protocol for assessing the effect of omega-3 supplementation on heart health. They conducted their clinical studies independently, and when their data (from 42,000 subjects) were pooled, the results showed that omega-3 supplementation decreased:

Premature death from all causes by 16%.
Premature death from heart disease by 19%.
Premature death from cancer by 15%.
Premature death from causes other than heart disease and cancer by 18%.

This study eliminates the limitations of previous meta-analyses. That makes it much stronger than the other meta-analyses. And these results are consistent with the current meta-analysis.

Omega-3s have long been recognized as essential nutrients. It is past time to set Daily Value (DV) recommendations for omega-3s. Based on the recommendations of other experts in the field, I think the DV should be set at 500-1,000 mg/day. I take more than that, but this would represent a good minimum recommendation for heart health.

Folic acid:

As with omega-3s, this meta-analysis reported a positive effect of folic acid on heart health. But many other studies have come up empty. Why is that?

It may be because, between food fortification and multivitamin use, many Americans already have sufficient blood levels of folic acid. For example, one study reported that 70% of the subjects in their study had optimal levels of folates in their blood. And that study also reported:

Subjects with adequate levels of folates in their blood received no additional benefit from folic acid supplementation.
However, for subjects with inadequate blood folate levels, folic acid supplementation decreased their risk of heart disease by ~15%.

We see this pattern over and over in supplement studies. Supplement opponents interpret these studies as showing that supplements are worthless. But a better interpretation is that supplements benefit those who need them.

The problem is that we don’t know our blood levels of essential nutrients. We don’t know which nutrients we need, and which we don’t. That’s why I like to think of supplements as “insurance” against the effects of an imperfect diet.

Vitamins E and D:

The situation with vitamins E and D is similar. This meta-analysis found no heart health benefit of either vitamin E or D. That is because the clinical studies included in the meta-analysis asked whether vitamin E or vitamin D improved heart health for everyone in the study.

Previous studies focusing on patients with low blood levels of these nutrients and/or at high risk of heart disease have shown some benefits of both vitamins at reducing heart disease risk.

So, for folic acid, vitamin E, and vitamin D (and possibly vitamin C) the take-home message should be:

Ignore all the Dr. Strangeloves telling you that these vitamins are “magic bullets” that will dramatically reduce your risk of heart disease.
Ignore the naysayers who tell you they are worthless.
Use supplementation wisely to make sure you have the recommended intake of these and other essential nutrients.

β-carotene:

This meta-analysis reported that β-carotene increased the risk of heart disease. This is not a new finding. Multiple previous studies have come to the same conclusion.

And we know why this is. There are many naturally occurring carotenoids, and they each have unique heart health benefits. A high dose β-carotene supplement interferes with the absorption of the other carotenoids. You are creating a deficiency of other heart-healthy carotenoids.

If you are not getting lots of colorful fruits and vegetables from your diet, my recommendation is to choose a supplement with all the naturally occurring carotenoids in balance – not a pure β-carotene supplement.

The Bottom Line

The Dr. Strangeloves in the nutrition space all have their favorite heart health supplements. They claim their supplements will single-handedly abolish heart disease (and help you leap tall buildings in a single bound).

On the other hand, many doctors will tell you these supplements are a waste of money. They don’t work. They just drain your wallet.

It’s so confusing. Who should you believe? Fortunately, a recent study has separated the hype from the hope and tells us which “heart-healthy” supplements work, and which don’t.

This study was a meta-analysis of 884 clinical studies with 883,627 participants. It reported:

Omega-3 supplementation deceased risk of heart attacks by 15% and all cardiovascular deaths by 7%.
Folic acid supplementation decreased stroke risk by 16%.
Coenzyme Q10 supplementation decreased the risk of all-cause mortality in patients with heart failure by 32%.
Vitamin C, vitamin E, vitamin D did not appear to affect heart disease outcomes.
β-carotene increased the risk of stroke, CVD mortality, and all-cause mortality.

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.

500th Issue Celebration

November 15, 2022 by Dr. Steve Chaney

Nutrition Breakthroughs Over The Last Two Years

Author: Dr. Stephen Chaney

In the nearly ten years that I have been publishing “Health Tips From The Professor”, I have tried to go behind the headlines to provide you with accurate, unbiased health information that you can trust and apply to your everyday life.

The 500^th issue of any publication is a major cause for celebration and reflection – and “Health Tips From The Professor” is no different.

I am dedicating this issue to reviewing some of the major stories I have covered in the past 100 issues. There are lots of topics I could have covered, but I have chosen to focus on three types of articles:

Articles that have debunked long-standing myths about nutrition and health.

Articles that have corrected some of the misinformation that seems to show up on the internet on an almost daily basis.

Articles about the issues that most directly affect your health.

Best Ways To Lose Weight

Since it is almost January, let’s start with a couple of articles about diet and weight loss (or weight gain). I have covered the effectiveness of the Paleo, Keto, Mediterranean, DASH, vegetarian, and Vegan diets for both short and long-term weight loss in my book “Slaying The Food Myths”, so I won’t repeat that information here. Instead, I will share a few updates from the past 100 issues.

My Tips On The Best Approach For Losing Weight: Every health guru has a favorite diet they like to promote. I am different. My book, Slaying the Food Myths, is probably the first “anti-diet” diet book ever written. Based on my years of research I can tell you that we are all different. There is no single diet that is best for everyone. In this article I have summarized my tips for selecting the weight loss diet that is best for you.

The US News & World Report’s Recommendation For the Best Diets: Each year US News & World Report assembles some of the top nutrition experts in the country and asks them to review popular diets and rank them for effectiveness and safety. In this article I summarize their ratings for 2022.

Does Intermittent Fasting Have A Downside? In previous articles in “Health Tips From the Professor” I have reported on studies showing that intermittent fasting is no more effective for weight loss than any other diet that restricts calories to the same extent. But does intermittent fasting have a downside? In this article I reported on a study that suggests it does.

Can A Healthy Diet Help You Lose Weight? Most investigators simply compare their favorite diet to the standard American diet. And any diet looks good compared to the standard American diet. In this article I reported on a study that compared two whole food diets that restricted calories by 25% to the standard American diet. One calorie-restricted diet was more plant-based and the other more meat-based. You may be surprised at the results.

Omega-3s

Omega-3s continue to be an active area of research. Here are just a few of the top studies over the past two years.

Do Omega-3s Oil Your Joints? In this article I reviewed the latest information on omega-3s and arthritis.

Do Omega-3s Add Years To Your Life? In this article I discussed a study that looks at the effect of omega-3s on longevity.

The Omega-3 Pendulum: In this article I discuss why omega-3 studies are so confusing. One day the headlines say they are miracle cures. A few weeks later the headlines say they are worthless. I discuss the flaws in many omega-3 studies and how to identify the high-quality omega-3 studies you can believe.

Do Omega-3s Reduce Congestive Heart Failure? In this article I review a recent study on omega-3s and congestive heart failure and discuss who is most likely to benefit from omega-3 supplementation.

Plant-Based Diets

Will Plant-Based Proteins Help You Live Longer? In this article I review a study that looks at the effect of swapping plant proteins for animal proteins on longevity.

Can Diet Add Years To Your Life? In this article I review a study that takes a broader view and asks which foods add years to your life.

Is A Vegan Diet The Secret To Weight Loss? This is an update of my previous articles on vegan diets. This article asked whether simply changing from a typical American diet to a vegan diet could influence weight loss and health parameters in as little as 16 weeks. The answer may surprise you.

Is A Vegan Diet Bad For Your Bones? No diet is perfect. This article looks at one of the possible downsides to a vegan diet. I also discuss how you can follow a vegan diet AND have strong bones. It’s not that difficult.

Anti-Inflammatory Diets

What Is An Anti-Inflammatory Diet? In this article I discuss the science behind anti-inflammatory diets and what an anti-inflammatory diet looks like.

Can Diet Cause You To Lose Your Mind? In this article I discuss a study looking at the effect of an inflammatory diet on dementia. The study also looks at which foods protect your mind and which ones attack your mind.

Do Whole Grains Reduce Inflammation? You have been told that grains cause inflammation. Refined grains might, but this study shows that whole grains reduce inflammation.

Nutrition And Pregnancy

Here are the latest advances in nutrition for a healthy pregnancy.

The Perils Of Iodine Deficiency For Women. In this article I reviewed the latest data showing that iodine is essential for a healthy pregnancy and discuss where you can get the iodine you need.

Do Omega-3s Reduce The Risk Of Pre-Term Births? You seldom hear experts saying that the data are so definitive that no further studies are needed. In this article I reviewed a study that said just that about omega-3s and pre-term births.

Does Maternal Vitamin D Affect ADHD? In this article I reviewed the evidence that adequate vitamin D status during pregnancy may reduce the risk of ADHD in the offspring.

How Much DHA Should You Take During Pregnancy? In this article I reviewed current guidelines for DHA intake during pregnancy and a recent study suggesting even higher levels might be optimal.

Is Your Prenatal Supplement Adequate? In this article I reviewed two studies that found most prenatal supplements on the market are not adequate for pregnant women or their unborn babies.

Children’s Nutrition

Here are the latest insights into children’s nutrition.

Are We Killing Our Children With Kindness? In this article I reviewed a recent study documenting the increase in ultra-processed food consumption by American children and the effect it is having on their health. I then ask, is it really kindness when we let our children eat all the sugar and ultra-processed food they want?

Is Diabetes Increasing In Our Children? In this article I reviewed a study documenting the dramatic increase in diabetes among American children and its relationship to ultra-processed food consumption and lack of exercise.

How Much Omega-3s Do Children Need? In this article I reviewed an study that attempts to define how much omega-3s are optimal for cognition (ability to learn) in our children.

Diabetes

Here are some insights into nutrition and diabetes that may cause you to rethink your diet.

Does An Apple A Day Keep Diabetes Away? You may have been told to avoid fruits if you are diabetic. In this article I reviewed a study showing that fruit consumption actually decreases your risk of diabetes. Of course, we are all different. If you have diabetes you need to figure out which fruits are your friends and which are your foes.

Do Whole Grains Keep Diabetes Away? You may have also been told to avoid grains if you are diabetic. In this article I reviewed a study showing that whole grain consumption actually decreases your risk of diabetes. Once again, we are all different. If you have diabetes you need to figure out which grains are your friends and which are your foes.

Heart Disease

Here is an interesting insight into nutrition and heart disease that may cause you to rethink your diet.

Is Dairy Bad For Your Heart? You have been told that dairy is bad for your heart AND that it is good for your heart. Which is correct? In this article I discuss some recent studies on the topic and conclude the answer is, “It depends”. It depends on your overall diet, your weight, your lifestyle, and your overall health.

Breast Cancer

Here are some facts about breast cancer every woman should know.

The Best Way To Reduce Your Risk Of Breast Cancer In this article I review two major studies and the American Cancer Guidelines to give you 6 tips for reducing your risk of breast cancer.

The Truth About Soy And Breast Cancer You have been told that soy causes breast cancer, and you should avoid it. In this article I review the science and tell you the truth about soy and breast cancer.

Supplementation

Some “experts” claim everyone should take almost every supplement on the market. Others claim supplementation is worthless. What is the truth about supplementation?

What Do The 2020-2025 Dietary Guidelines Say About Supplements? Every 5 years the USDA updates their Dietary Guidelines for foods and supplements. In this article I discuss what the 2020-2025 Dietary Guidelines say about supplements. Yes, the USDA does recommend supplements for some people.

Who Benefits Most From Supplementation? Not everyone benefits equally from supplementation. In this article I discuss who benefits the most from supplementation.

Should Cancer Patients Take Supplements? Doctors routinely tell their cancer patients not to take supplements. Is that the best advice? In this article I review a study that answers that question.

Can You Trust Supplements Marketed on Amazon? Amazon’s business model is to sell products at the lowest possible price. But do they check the quality of the products marketed on their site? In this article I review a study that answers that question.

Is Your Prenatal Supplement Adequate? In this article I reviewed two studies that found most prenatal supplements on the market are not adequate for pregnant women or their unborn babies.

The Bottom Line

I have just touched on a few of my most popular articles above. You may want to scroll through these articles to find ones of interest to you that you might have missed over the last two years. If you don’t see topics that you are looking for, just go to https://chaneyhealth.com/healthtips/ and type the appropriate term in the search box.

In the coming years, you can look for more articles debunking myths, exposing lies and providing balance to the debate about the health topics that affect you directly. As always, I pledge to provide you with scientifically accurate, balanced information that you can trust. I will continue to do my best to present this information in a clear and concise manner so that you can understand it and apply it to your life.

Final Comment: You may wish to share the valuable resources in this article with others. If you do, then copy the link at the top and bottom of this page into your email. If you just forward this email and the recipient unsubscribes, it will unsubscribe you as well.

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?

September 13, 2022 by Dr. Steve Chaney

Which Diet Is Best?

Author: Dr. Stephen Chaney

Alzheimer’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?

The 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?

Here 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?

In 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?

The 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?

The 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.

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.

How Much Omega-3s Do Children Need?

September 6, 2022 by Dr. Steve Chaney

What Does This Study Mean For Your Children?

Author: Dr. Stephen Chaney

It is back to school time again. If you have children, you are probably rushing around to make sure they are ready.

Backpack…Check.
Books…Check
School supplies…Check
Omega-3s…???

Every parent wants their child to do their best in school. But do they need omega-3s to do their best? I don’t need to tell you that question is controversial.

Some experts claim that omega-3 supplementation in children improves their cognition. [Note: Cognition is defined as the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses. In layman’s terms that means your child’s ability to learn.]

Other experts point out that studies in this area disagree. Some studies support these claims. Others don’t. Because the studies disagree these experts conclude there is no good evidence to support omega-3 supplementation in children.

The authors of this study (ISM van der Wurff et al, Nutrients, 12: 3115, 2020) took a different approach. They asked why these studies disagreed. They hypothesized that previous studies disagreed because there is a minimal dose of omega-3s needed to achieve cognitive benefits in children. In short, they were asking how much omega-3s do children need.

They based their hypothesis on recent studies showing that a minimum dose of omega-3s is required to show heart health benefits in adults.

What Have We Learned From Studies on Omega-3s And Heart Health?

The breakthrough in omega-3/heart health studies came with the development of something called the omega-3 index. Simply put, omega-3s accumulate in our cell membranes. The omega-3 index is the percent omega-3s in red blood cell membranes and is a good measure of our omega-3 status.

Once investigators began measuring the omega-3 index in their studies and correlating it with heart health, it became clear that:

An omega-3 index of ≤4% correlated with a high risk of heart disease.

An omega-3 index of ≥8% correlated with a low risk of heart disease.

Most Americans have an omega-3 index in the 4-6% range.

Clinical studies in which participants’ omega-3 index started in the low range and increased to ~8% through supplementation generally showed a positive effect of omega-3s on reducing heart disease risk. [I say generally because there are other factors in study design that can obscure the effect of omega-3s.]

This is the model that the authors adopted for their study. They asked how much omega-3s do children need to show a positive effect of omega-3s on their cognition (ability to learn).

How Was The Study Done?

The authors included 21 studies in their analysis that met the following criteria:

All studies were placebo controlled randomized clinical trials.

The participants were 4-25 years old and had not been diagnosed with ADHD.

Supplementation was with the long-chain omega-3s DHA and/or EPA.

The trial assessed the effect of omega-3 supplementation on cognition.

I do not want to underestimate the difficulties the authors faced in their quest. The individual studies differed in:

The dose of omega-3s.

- The relative amount of DHA and EPA.

- Whether omega-3 index was measured. Only some of the studies measured fatty acid levels in the blood. The authors were able to calculate the omega-3 index in these studies.

How cognition (ability to learn) was measured.

The age of the children.

- 20 of the studies were done with children (4-12 years old) or late adolescents (20-25 years old).

- Only one study was done on early to middle adolescents (12-20 years old).

All these variables influence the outcome and could obscure the effect of omega-3s on cognition.

In short, determining the omega-3 dose-response for an effect on cognition was a monumental task. It was like searching for a needle in a haystack. These authors did a remarkable job.

How Much Omega-3s Do Children Need?

Here is what the scientists found when they analyzed the data:

60% of the studies in which an omega-3 index of ≥6% was achieved showed a beneficial effect of omega-3 supplementation on cognition (ability to learn) compared to 20% of the studies that did not achieve an omega-3 index of 6%.

- That is a 3-fold difference in effectiveness once a threshold of 6% omega-3 index was reached.

50% of the studies in which a dose of ≥ 450 mg/day of DHA + EPA was used showed a beneficial effect of omega-3 supplementation on cognition (ability to learn) compared to 25% of the studies that used <450 mg/day DHA + EPA.

- That is a 2-fold difference in effectiveness once a threshold of 450 mg/day DHA + EPA was given.

The authors concluded, “Daily supplementation of ≥450 mg/day DHA and/or EPA and an increase in the omega-3 index to >6% makes it more likely to show efficacy [of omega-3s] on cognition (ability to learn) in children and adolescents.”

What Does This Study Tell Us?

It is important to understand what this study does and does not tell us.

This study does not:

Prove that omega-3 supplementation can improve cognition (ability to learn) in children and adolescents.

Define optimal levels of DHA + EPA.

Tell us whether DHA, EPA, or a mixture is better.

It was not designed to do any of these things. It was designed to give us a roadmap for future studies. It tells us how to design studies that can provide definitive answers to these questions.

This study does:

Define a threshold dose of DHA + EPA for future studies (450 mg/day).

Tells us how to best use the omega-3 index in future studies. To obtain meaningful results:

- Participants should start with an omega-3 index of 4% or less.

- Participants should end with an omega-3 index of 6% or greater.

In my opinion, future studies would also be much more effective if scientists in this area of research could agree on a single set of cognitive measures to be used in all subsequent studies.

In short, this study provides critical information that can be used to design future studies that will be able to provide definitive conclusions about omega-3s and cognition in children.

What Does This Study Mean For Your Children?

As a parent or grandparent, you probably aren’t interested in optimizing the design of future clinical studies. You want answers now.

Blood tests for omega-3 index are available, but they are not widely used. And your insurance may not cover them.

So, for you the most important finding from this study is that 450 mg/day DHA + EPA appears to be the threshold for improving a child’s cognition (their ability to learn).

450 mg/day is not an excessive amount. The NIH defines adequate intakes for omega-3s as follows:

4-8 years: 800 mg/day
9-13 years: 1 gm/day for females, 1.2 gm/day for males
14-18 years: 1.1 gm/day for females and 1.6 gm/day for males.
With at least 10% of that coming from DHA + EPA

Other organizations around the world recommend between 100 mg/day and 500 mg/day DHA + EPA depending on the age and weight of the child and the organization.

Most children need supplementation to reach adequate omega-3 intake. The NIH estimates the average child only gets around 40 mg/day omega-3s from their diet. No matter which recommendation you follow, it is clear that most children are not getting the recommended amount of DHA + EPA in their diet.

Genetics.
Diet.
Environment.
The value placed on learning by parents and peers.

Supplementation is just one factor in your child’s ability to learn. But it is one you can easily control. . And if your child is like most, he or she is probably not getting enough omega-3s in their diet.

The Bottom Line

It is back to school time again. Every parent wants their child to do their best in school. But do they need omega-3s to do their best? I don’t need to tell you that question is controversial.

Some studies support these claims, but others don’t. Because the studies disagree some experts conclude there is no good evidence to support omega-3 supplementation in children.

The authors of a recent study took a different approach. They asked why these studies disagreed. They hypothesized that previous studies disagreed because there was a minimal dose of omega-3s needed to achieve cognitive benefits in children. They asked how much omega-3s children need.

They analyzed the data from 21 previous studies looking at the effect of omega-3 supplementation on cognition (ability to learn) in children and adolescents. Their analysis showed:

60% of the studies in which an omega-3 index of ≥6% was achieved showed a beneficial effect of omega-3 supplementation on cognition (ability to learn) compared to 20% of the studies that did not achieve an omega-3 index of 6%.

- That is a 3-fold difference in effectiveness once a threshold of 6% omega-3 index was reached.

50% of the studies in which a dose of ≥ 450 mg/day of DHA + EPA was used showed a beneficial effect of omega-3 supplementation on cognition (ability to learn) compared to 25% of the studies that used <450 mg/day DHA + EPA.

- That is a 2-fold difference in effectiveness once a threshold dose of 450 mg/day DHA + EPA was given.

The authors concluded, “Daily supplementation of ≥450 mg/day DHA + EPA and an increase in the omega-3 index to >6% makes it more likely to show efficacy [of omega-3s] on cognition (ability to learn) in children and adolescents.”

For more details on the study and what it means for your children and grandchildren, 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.

Omega-3s Reduce Preterm Births

August 9, 2022 by Dr. Steve Chaney

Do Omega-3s Make For A Healthy Pregnancy?

Author: Dr. Stephen Chaney

The role of omega-3s on a healthy pregnancy has been in the news for some time. Claims have been made that omega-3s reduce preterm births, postnatal depression, and improve cognition, IQ, vision, mental focus, language, and behavior in the newborn as they grow.

The problem is that almost all these claims have been called into question by other studies. If you are pregnant or thinking of becoming pregnant, you don’t know what to believe.

Should you eat more fish?
Should you take omega-3 supplements?
Or should you just ignore the claims about omega-3s and a healthy pregnancy?

These are not trivial questions. Let’s consider preterm births as an example. The medical profession has made enormous advances in keeping premature babies alive. However, premature babies are still at higher risk of several health conditions including:

Visual impairment.
Developmental Delay.
Learning difficulties.

Plus, it is expensive to keep premature babies alive. One recent study estimated that increasing omega-3 intake during pregnancy could reduce health care costs by around $6 billion in the United Stated alone.

Unfortunately, it’s not just omega-3s and pregnancy. The same is true for almost all nutritional health claims. One day a study comes out claiming that nutrient “X” cures some disease or has some miraculous benefit. The bloggers and news media hype that study. Suddenly you see that health claim everywhere. It becomes so omnipresent that you are tempted to believe it must be true.

But wait. A few months later another study comes to opposite conclusion. Now the media is telling you that health claim is false. The months come and go, and new studies keep coming out. Some support the health claim. Others refute it.

Pretty soon the nutrition headlines just become “noise”. You don’t know what to believe. If you want the truth, “Who ya gonna call?”

Who Ya Gonna Call?

It’s not Ghostbusters. It not Dr. Strangelove’s health blog. It’s a group called the Cochrane Collaboration.

The Cochrane Collaboration consists of 30,000 volunteer scientific experts from across the globe whose sole mission is to analyze the scientific literature and publish reviews of health claims so that health professionals, patients, and policy makers can make evidence-based choices about health interventions.

The Cochrane Collaboration reviews all the relevant studies on a topic, exclude those that are biased or weak, and make their recommendations based on only the strongest studies. Their reviews are considered the gold standard of evidence-based medicine.

If you are of a certain age, you may remember that TV commercial “When EF Hutton talks, people listen.” It is the same with the Cochrane Collaboration. When they talk, health professionals listen.

This week we will examine the Cochrane Collaboration’s review titled “Omega-3 Fatty Acid Addition During Pregnancy”.

How Was The Study Done?

For this analysis the Cochrane Collaboration reviewed 70 randomized controlled trials which compared the effect of added omega-3s on pregnancy outcomes with either a placebo or a diet no added omega-3s. These trials included almost 19,927 pregnant women.

In one sense, Cochrane reviews are what is called a “meta-analysis”, in which data from numerous studies are grouped together so that a statistically significant conclusion can be reached. However, Cochrane Collaboration reviews differ from most meta-analyses found in the scientific literature in a very significant way.

Many published meta-analyses simply report “statistically significant” conclusions. However, statistics can be misleading. As Mark Twain said: “There are lies. There are damn lies. And then there are statistics”.

The problem is that the authors of most meta-analyses group studies together without considering the quality of studies included in their analysis. This creates a “Garbage In – Garbage Out” effect. If the quality of individual studies is low, the quality of the meta-analysis will also be low. Simply put, the conclusions from some published meta-analyses are not worth the paper they are written on.

The Cochrane Collaboration also reports statistically significant conclusions from their meta-analyses. However, they also carefully consider the quality of each individual study in their analysis. They look at possible sources of bias. They look at the design and size of the studies. Finally, they ask whether the conclusions are consistent from one study to the next. They clearly define the quality of evidence that backs up each of their conclusions as follows:

High-quality evidence. Further research is unlikely to change their conclusion. This is generally reserved for conclusions backed by multiple high-quality studies that have all come to the same conclusion. These are the recommendations that are most often adopted into medical practice.

Moderate-quality evidence. This conclusion is likely to be true, but further research could have an impact on it.

Low-quality evidence. Further research is needed and could alter the conclusion. They are not judging whether the conclusion is true or false. They are simply saying more research is needed to reach a definite conclusion.

Omega-3s Reduce Preterm Births

Here are the conclusions that the Cochrane Collaboration said were supported by high-quality evidence:

Omega-3s reduce the risk of preterm births.

Omega-3s reduce the risk of low-birth-weight infants.

The authors concluded: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the risk of preterm birth…More studies comparing omega-3s and placebo are not needed at this point.”

In other words, they are saying this conclusion is definite. Omega-3 supplementation should become part of the standard of medical care for pregnant women.

However, they did say that further studies were needed “…to establish if, and how, outcomes vary by different types of omega-3s, timing [stage of pregnancy], doses [of omega-3s], or by characteristics of women.”

That’s because these variables were not analyzed in the Cochrane study. Their review and meta-analysis included clinical trials:

Of women at low, moderate, and high risk of poor pregnancy outcomes.

With DHA alone, with EPA alone, and with a mixture of both.

Omega-3 doses that were low (˂ 500 mg/day), moderate (500-1,000 mg/day), and high (> 1,000 mg/day).

Do Omega-3s Make For A Healthy Pregnancy?

What about the effect of omega-3s on other pregnancy outcomes?

The conclusions the Cochrane Collaboration said were supported by moderate quality evidence included reductions in:

Perinatal death.

Admissions to the neonatal intensive care unit.

There was not enough high or moderate quality data to determine the effect of omega-3s on other pregnancy outcomes such as postnatal depression. More research is still needed in those areas. However, if you do receive any of these benefits from omega-3 supplementation, you can just consider them as side benefits.

What Does This Report Mean For You?

1) The proven effect of omega-3 supplementation on preterm births is significant because preterm births increase the risk of:

Visual impairment.
Developmental Delay.
Learning difficulties.

2) The likely effect of omega-3s on admission to neonatal intensive care units is significant because those units are very expensive.

3) The Cochrane study did not determine whether omega-3 supplementation was equally important for women at low, moderate, and high likelihood of poor pregnancy outcomes.

Therefore, omega-3 supplementation should be considered for all pregnant women.

4) The Cochrane study did not determine whether omega-3 supplementation was equally important during the first, second, or third trimester.

Therefore, omega-3 supplementation should be considered by all women of childbearing age who might become pregnant and throughout pregnancy.

5) The Cochrane study did not determine whether DHA, EPA, or a mixture of the two was most effective.

Therefore, your omega-3 supplement should probably contain both DHA and EPA. A group of experts recently recommended that adults consume at least 650 mg/day of omega-3s with ≥ 220 mg of that coming from DHA and ≥ 220 mg/day coming from EPA.

Since most pregnant women in this country consume around 89 mg/day of DHA + EPA, omega-3 supplementation is warranted.

The Bottom Line

The effect of omega-3s on pregnancy outcomes have been confusing. Some studies conclude that omega-3s are important for a healthy pregnancy. Other studies suggest they are ineffective. What are you to believe?

Fortunately, a group called the Cochrane Collaboration recently conducted a comprehensive review of this topic. This is significant because Cochrane Reviews are internationally recognized as the highest standard in evidence-based health care. They influence the treatment protocols recommended by the medical community.

This Cochrane Review concluded that omega-3 supplementation during pregnancy:

Reduces preterm births and low birth weight infants.

Likely reduces perinatal death and admissions to the neonatal intensive care unit.

The authors of the review said: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the risk of preterm birth…More studies comparing omega-3s and placebo are not needed at this point.”

In other words, they are saying this conclusion is definite. Omega-3 supplementation should become part of the standard of medical care for pregnant women.

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.

Omega-3s And Congestive Heart Failure

May 3, 2022 by Dr. Steve Chaney

We Have Been Asking The Wrong Questions

Author: Dr. Stephen Chaney

Today’s Health Tip is a follow-up to the article I published last month on omega-3s and heart disease risk. In that article I pointed out the reasons why studies of the effect of omega-3s and heart disease risk have been so confusing.

One of the reasons is that many of the studies have been asking the wrong questions.

They were asking whether omega-3s reduced the risk of heart disease for everyone. Instead, they should have been asking who benefited from omega-3 supplementation.

They were asking whether omega-3s reduced the risk of all forms of heart disease combined. Instead, they should have been asking whether omega-3s reduced the risk of specific kinds of heart disease.

I also discussed a large clinical trial, the VITAL study, that was designed to answer those two questions.

The study I will describe today (L Djoussé et al, JACC Heart Failure, 10: 227-234, 2022) mined the data from the VITAL study to evaluate the effect of omega-3 supplementation on congestive heart failure, a form of heart disease that was not discussed in the VITAL study.

Everything You Need To Know About Congestive Heart Failure

Congestive heart failure is a killer. The term congestive heart failure simply means that your heart no longer pumps blood well. The initial symptoms are relatively non-specific and include things like.

Shortness of breath.
Fatigue and weakness.
Reduced ability to exercise.
Rapid or irregular heartbeat.
Persistent cough or wheezing.

However, as it progresses, the symptoms get much worse. Fluid builds up in your tissues.

Fluid buildup in your legs, ankles, and feet can make it difficult to walk.

Fluid buildup in your lungs makes it difficult to breathe. In advanced stages it can feel like you are drowning in a room full of air.

According to the CDC:

4 million Americans have congestive heart failure (CHF).

- It leads to ~380,000 deaths/year.

83% of patients diagnosed with CHF will be hospitalized at least once.

- 67% will be hospitalized two or more times.

CHF costs >$30 billion per year in health care costs and lost wages.

The risk of congestive heart failure is not spread evenly across the American population. Black Americans and Americans with type 2 diabetes are at increased risk.

According to the Framingham Heart Study:

Type 2 diabetes increases the risk of CHF 2-fold in men and 5-fold in women. The reasons are not entirely clear. However:

- High blood sugar is thought to either damage cells in heart muscle, weakening it, or damage small blood vessels within the heart, making it more difficult for the heart to pump blood.

- Some diabetes drugs that lower blood sugar also appear to increase the risk of congestive heart failure.

According to the CDC:

Black Americans are 2-fold more likely to develop CHF than White Americans. Again, the reasons are not clear. However:

- Some experts feel it could be due to the higher incidence of untreated high blood pressure in Black Americans.

In summary:

Congestive heart failure is a serious disease. Its symptoms affect your quality of life, and it can lead to hospitalizations and death.

Black Americans and Americans with type 2 diabetes are at higher risk of developing congestive heart failure.

How Was The Study Done?

The VITAL study, from which these data were extracted, was a placebo-controlled clinical trial designed to measure the effects of 1,000 mg omega-3 supplementation on the risk of developing heart disease. It enrolled 25,871 Americans aged 55 years or older and followed them for an average of 5.3 years.

The participants enrolled in the VITAL study represented a cross-section of the American population. Most were at low risk of heart disease, but there were subsets of the study group who were at higher risk of heart disease. A strength of the VITAL study was that it was designed so the high-risk subgroups could be evaluated separately.

The current study utilized data from the VITAL study to look at the effect of omega-3 supplementation on hospitalizations due to congestive heart failure. It also evaluated the effect of type 2 diabetes and race on the risk of hospitalizations.

Omega-3s And Congestive Heart Failure

When the investigators looked at the whole population, most of whom were at low-risk of congestive heart failure, they did not see any effect of omega-3 supplementation on the risk of hospitalizations due to congestive heart failure.

However, when they looked at high risk groups, the story was much different.

In patients with type-2 diabetes:

Omega-3 supplementation reduced the risk of the initial hospitalization for congestive heart failure by 31%

Omega-3 supplementation reduced the risk of multiple hospitalizations due to congestive heart failure by 47%.

The effect of omega-3 supplementation on hospitalizations was greatest for the Black participants in the study.

In the words of the authors, “Our data show beneficial effects of omega-3 fatty acid supplements on the incidence of heart failure hospitalizations in participants with type 2 diabetes but not in those without type 2 diabetes, and such benefit appeared to be stronger in Black participants with type 2 diabetes.”

We Are Asking The Wrong Questions

As I said above, there is so much confusion about the effect of omega-3s on heart disease because we scientists have been asking the wrong questions:

We have been asking whether omega-3s reduce the risk of heart disease for everyone. Instead, we should have been asking who benefits from omega-3 supplementation.

We have been asking whether omega-3s reduced the risk of all forms of heart disease combined. Instead, we should have been asking whether omega-3s reduced the risk of specific kinds of heart disease.

In my “Health Tip” last month I discussed a large clinical study, the VITAL study, that was specifically designed to answer the right questions. Like so many other studies it found that omega-3 supplementation did not significantly reduce the risk of all kinds of heart disease for everyone.

However, what it did find was more important than what it did not find:

When they looked at the effect of omega-3s on heart disease risk in high-risk groups, they found that major cardiovascular events were reduced by:

- 26% in African Americans.

- 26% in patients with type 2 diabetes.

- 17% in patients with a family history of heart disease.

- 19% in patients with two or more risk factors of heart disease.

When they looked at the effect of omega-3s on heart disease risk in people with low omega-3 intake, they found that omega-3 supplementation reduced major cardiovascular events by:

- 19% in patients with low fish intake.

When they looked at the effect of omega-3s on the risk of different forms of heart disease, they found that omega-3 supplementation reduced:

- Heart attacks by 28% in the general population and by 70% for African Americans.

- Deaths from heart attacks by 50%.

- Deaths from coronary heart disease (primarily heart attacks and ischemic strokes (strokes caused by blood clots)) by 24%.

In other words, when they asked the wrong questions, they got the wrong answer. If they had just looked at the effect of omega-3 supplementation on all forms of heart disease for everyone (like most other omega-3 studies), they would have concluded that omega-3s are worthless.

However, when they asked the right questions, they found that omega-3s were very beneficial for high-risk populations and for certain types of heart disease.

The current study utilized the same data to analyze the effect of omega-3 supplementation on hospitalizations due to congestive heart failure. And the results were similar.

If they had asked the wrong question, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for everyone?”, they would have concluded that omega-3 supplementation was worthless.

However, instead they asked, “Does omega-3 supplementation reduce congestive heart failure hospitalizations for certain high-risk groups” and were able to show that omega-3 supplementation significantly reduced congestive heart failure hospitalizations for people with type 2 diabetes and for Blacks.

We need to change the paradigm for clinical studies of supplements. The old paradigm asks the wrong questions. If we really want to know the role of supplementation for our health, we need to start asking the right questions.

The Bottom Line

There is perhaps nothing more confusing to the average person than the “truth” about omega-3 supplementation and heart disease risk. Much of the confusion is because we have been asking the wrong questions:

We have been asking whether omega-3 supplementation reduces the risk of heart disease for everyone. Instead, we should have been asking who benefits from omega-3 supplementation.

We have been asking whether omega-3 supplementation reduces the risk of all forms of heart disease combined. Instead, we should have been asking whether omega-3 supplementation reduces the risk of specific kinds of heart disease.

A recent study on the effect of omega-3 supplementation on hospitalizations due to heart disease is a perfect example.

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.

The Omega-3 Pendulum

April 12, 2022 by Dr. Steve Chaney

Who Benefits Most From Omega-3s?

Author: Dr. Stephen Chaney

If you were around in the 60’s, you might remember the song “England Swings Like a Pendulum Do”. It was a cute song, but it had nothing to do with pendulums. This week I am talking about something that really does resemble a pendulum – the question of whether omega-3s reduce heart disease risk.

There is perhaps nothing more confusing to the average person than the “truth” about omega-3s and heart disease risk. The headlines and expert opinion on the topic swing wildly between “omega-3s reduce heart disease risk” to “omega-3s have no effect on heart disease risk” and back again. To me these swings resemble the swings of a pendulum – hence the title of this article.

Part of the reason for the wild swings is that journalists and most “experts” tend to rely on the latest study and ignore previous studies. Another contributing factor is that most journalists and experts read only the main conclusions in the article abstract. They don’t read and analyze the whole study.

So, in today’s “Health Tips From the Professor” I plan to:

Analyze 3 major studies that have influenced our understanding of the relationship between omega-3 intake and heart disease risk. I will tell you what the experts missed about these studies and why they missed it.

Summarize what you should know about omega-3 intake and your risk of heart disease.

Why Is The Role Of Omega-3s In Preventing Heart Disease So Confusing?

In answering that question, let me start with what I call “Secrets Only Scientists Know”.

#1: Each study is designed to disprove previous studies. That is a strength of the scientific method. But it guarantees there will be studies on both sides of every issue.

Responsible scientists look at all high-quality studies and base their opinions on the weight of evidence. Journalists and less-responsible “experts” tend to “cherry pick” the studies that match their opinions.

#2: Every study has its flaws. Even high-quality studies have unintended flaws. And I have some expertise in identifying unintended flaws.

I published over 100 papers that went through the peer review process. And I was involved in the peer review of manuscripts submitted by other scientists. In the discussion below I will use my experience in reviewing scientific studies to identify unintended flaws in 3 major studies on omega-3s and heart disease risk.

Next, let me share the questions I ask when reviewing studies on omega-3s and heart disease. I am just sharing the questions here. Later I will share examples of how these questions allowed me to identify unintended flaws in the studies I review below.

#1: How did they define heart disease? The headlines you read usually refer to the effect of omega-3s on “heart disease”. However, heart disease is a generic term. In layman’s terms, it encompasses angina, heart attacks, stroke due to blood clots, stroke due brain bleeds, congestive heart failure, impaired circulation, and much more.

Omega-3s have vastly different effects on different forms of heart disease, so it is important to know which form(s) of heart disease the study examined. And if the study included all forms of heart disease, it is important to know whether they also looked at the forms of heart disease where omega-3s have been shown to have the largest impact.

#2: What was the risk level of the patients in the study? If the patients in the study are at imminent risk of a heart attack or major cardiovascular event, it is much easier to show an effect than if they are at low risk.

For example, it is easy to show that statins reduce the risk of a second heart attack in someone who has just suffered a heart attack. These are high-risk patients. However, if you look at patients with high cholesterol but no other risk factors for heart disease, it is almost impossible to show a benefit of statins. These are low-risk patients.

If it is difficult to show that statins benefit low-risk patients, why should we expect to be able to show that omega-3s benefit low-risk patients?

[Note: I am not saying that statins do not benefit low-risk patients. I am just saying it is very difficult to prove they do in clinical studies.]

#3: How much omega-3s are the patients getting in their diet? The public reads the headlines. When the headlines say that omega-3s are good for their hearts, they tend to take omega-3 supplements. When the headlines say omega-3s are worthless, they cut back on omega-3 supplements. So, there is also a pendulum effect for omega-3 intake.

Omega-3s are fats. So, omega-3s accumulate in our cell membranes. The technical term for the amount of omega-3s in our cellular membranes is something called “Omega-3 Index”. Previous studies have shown that:

- An omega-3 index of 4% or less is associated with high risk of heart disease, and…

- An omega-3 index of 8% or more is associated with a low risk of heart disease.

When the omega-3 index approaches 8%, adding more omega-3 is unlikely to provide much additional benefit. Yet many studies either don’t measure or ignore the omega-3 index of patients they are enrolling in the study.

#4: How many and what drugs were the patients taking? Many heart disease patients are taking drugs that lower blood pressure, lower triglycerides, reduce inflammation, and reduce the risk of blood clot formation. These drugs do the same things that omega-3s do. This decreases the likelihood that you can see any benefit from increasing omega-3s intake.

The Omega-3 Pendulum

With all this in mind let’s examine three major double-blind, placebo-controlled studies that looked at the effect of omega-3s on heart disease risk and came to different conclusions. Here is a summary of the studies.

GISSI Study	ASCEND Study	VITAL Study
11,000 participants	15,480 participants	25,871 participants
Followed for 3.5 years	Followed for 7.4 years	Followed for 5.3 years
Europe	USA	USA
Published in 1999	Published in 2018	Published in 2019
Dose = 1 gm/day	Dose = 1 gm/day	Dose = 1 gm/day
20% ↓ in heart disease deaths	No effect on fatal or non-fatal heart attack or stroke	Significant ↓ in some forms of heart disease
45% ↓ in fatal heart attack or stroke – as effective as statins		Significant ↓ in heart disease risk for some patients

At first glance the study designs look similar, so why did these studies give such different results. This is where the unintended flaws come into play. Let’s look at each study in more detail.

The GISSI Study:

The patients enrolled in this study all had suffered a heart attack in the previous 3 months. They were at very high risk of suffering a second heart attack within the next couple of years.

Omega-3 intake was not measured in this study. But it was uncommon for Europeans to supplement with omega-3s in the 90’s. And European studies on omega-3 intake during that period generally found that omega-3 intake was low.

Patients enrolled in this study were generally taking only 2 heart disease drugs, a beta-blocker and a blood pressure drug.

The ASCEND Study:

The patients enrolled in this study had diabetes without any evidence of heart disease. Only 17% of the patients enrolled in the study were at high risk of heart disease. 83% were at low risk. Remember, it is difficult to show a benefit of any intervention in low-risk patients.

The average omega-3 index of patients enrolled in this study was 7.1%. That means omega-3 levels were near optimal at the beginning of the study. Adding additional omega-3s was unlikely to show much benefit.

Most of the patients in this study were on 3-5 heart drugs and 1-2 diabetes drugs which duplicated the effects of omega-3s.

That means this study was asking a very different question. It was asking whether omega-3s provided any additional benefit for patients who were already taking multiple drugs that duplicated the effects of omega-3s.

However, you would have never known that from the headlines. The headlines simply said this study showed omega-3s were ineffective at preventing heart disease.

Simply put, this study was doomed to fail. However, despite its many flaws the authors reported that omega-3s did reduce one form of heart disease, namely vascular deaths (primarily due to heart attack and stroke). Somehow this observation never made it into the headlines.

The VITAL Study:

This study enrolled a cross-section of the American population aged 55 or older (average age = 67). As you might suspect for a cross-section of the American population, most of the participants in this study were at low risk for heart disease. This limited the ability of the study to show a benefit of omega-3 supplementation in the whole population.

However, there were subsets of the group who were at high risk of heart disease (more about that below).

This study excluded omega-3 supplement users The average omega-3 index of patients enrolled in this study was 2.7% at the beginning of the study and increased substantially during the study. This enhanced the ability of the study to show a benefit of omega-3 supplementation.

Participants in this study were only using statins and blood pressure medications. People using more medications were excluded from the study. This also enhanced the ability of the study to show a benefit of omega-3 supplementation.

The authors reported that “Supplementation with omega-3 fatty acids did not result in a lower incidence of major cardiovascular events…” This is what lazy journalists and many experts reported about the study.

However, the authors designed the study so they could also:

Look at the effect of omega-3s on heart disease risk in high-risk groups. They found that major cardiovascular events were reduced by:

- 26% in African Americans.

- 26% in patients with diabetes.

- 17% in patients with a family history of heart disease.

- 19% in patients with two or more risk factors of heart disease.

Look at the effect of omega-3s on heart disease risk in people with low omega-3 intake. They found that omega-3 supplementation reduced major cardiovascular events by:

- 19% in patients with low fish intake.

Look at the effect of omega-3s on the risk of different forms of heart disease. They found that omega-3 supplementation reduced:

- Heart attacks by 28% in the general population and by 70% for African Americans.

- Deaths from heart attacks by 50%.

- Deaths from coronary heart disease (primarily heart attacks and ischemic strokes (strokes caused by blood clots)) by 24%.

In summary, if you take every study at face value it seems like the pendulum is constantly swinging from “omega-3s reduce heart disease risk” to “omega-3s are worthless” and back again. There appears to be no explanation for the difference in results from one study to the next.

However, if you remember that even good studies have unintended flaws and ask the four questions I proposed above, it all makes sense.

How is heart disease defined? Studies looking at heart attack and/or ischemic stroke are much more likely to show a benefit of omega-3s than studies that include all forms of heart disease.

Are the patients at low-risk or high-risk for heart disease? Studies in high-risk populations are much more likely to show a benefit than studies in low-risk populations.

What is the omega-3 intake of participants in the study? Studies in populations with low omega-3 intake are more likely to show a benefit of omega-3 supplementation than studies in populations with high omega-3 intake.

How many heart drugs are the patients taking? Studies in people taking no more than one or two heart drugs are more likely to show a benefit of omega-3 supplementation than studies in people taking 3-5 heart drugs.

When you view omega-3 clinical studies through the lens of these 4 questions, the noise disappears. It is easy to see why these studies came to different conclusions.

Who Benefits Most From Omega-3s?

The answers to this question are clear:

People at high risk of heart disease are most likely to benefit from omega-3 supplementation.

People with low omega-3 intake are most likely to benefit from omega-3 supplementation.

Omega-3 supplementation appears to have the biggest effect on heart attack and ischemic stroke (stroke due to blood clots). Its effect on other forms of heart disease is less clear.

Omega-3 supplementation appears to be most effective at preventing heart disease if you are taking no more than 1 or 2 heart drugs. It may provide little additional benefit if you are taking multiple heart drugs. However, you might want to have a conversation with your doctor about whether omega-3 supplementation might allow you to reduce or eliminate some of those drugs.

What about the general population? Is omega-3 supplementation useful for patients who are at low to moderate risk of heart disease?

If we compare omega-3 studies with statin studies, the answer would be yes. Remember that statins cannot be shown to reduce heart attacks in low-risk populations. However, because they are clearly effective in high-risk patients, the medical community assumes they should be beneficial in low-risk populations. The same argument could be made for omega-3s.

We also need to recognize that our ability to recognize those who are at high risk of heart disease is imperfect. For too many Americans, the first indication that they have heart disease is sudden death!

When I was still teaching, I invited a cardiologist to speak to my class of first year medical students. He told the students, only partly in jest, that he felt statins were so beneficial they “should be added to the drinking water”.

I feel the same way about omega-3s:

Most Americans do not get enough omega-3s in our diet.

Our omega-3 index is usually much closer to 4% (high risk of heart disease) than 8% (low risk of heart disease).

Many of us may not realize that we are at high risk of heart disease until it is too late.

And omega-3s have other health benefits.

For all these reasons, omega-3 supplementation only makes sense.

The Bottom Line

If you take every study at face value, there appears to be no explanation for the difference in results from one study to the next. However, if you recognize that even good studies have unintended flaws and ask four simple questions to expose these flaws, it all makes sense.

For the four questions you should ask when reviewing any omega-3 study and my recommendations for who benefits the most from omega-3 supplementation, read the article above.

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

Is Low Omega-3 Intake As Bad For You As Smoking?

August 31, 2021 by Dr. Steve Chaney

What Is The Omega-3 Index And Why Is It Important?

Author: Dr. Stephen Chaney

We already know that smoking is one of the worst things we can do to our bodies. It dramatically increases our risk of cancer, heart disease, diabetes, and lung diseases, including chronic obstructive pulmonary disease (COPD).

It also leads to premature death. People who smoke regularly die 5 years earlier than those who don’t.

That is the bad news. The good news is that smoking is what is called a “modifiable risk factor”. Simply put, that means it is a risk factor we are in control of. The message has been clear for years.

If you don’t smoke, keep it that way.

If you do smoke, stop. If you are a smoker, quitting isn’t easy, but it is worth it. The damage caused by smoking can largely be reversed if you stay off cigarettes long enough.

Obesity and diabetes are also modifiable risk factors that have a huge effect on the risk of both heart disease and premature death. People with diabetes die 4 years earlier than those without diabetes. But obesity and diabetes are harder for most people to reverse than smoking.

Diet is another modifiable risk factor, but, in general, its effect on the risk of heart disease and premature death is not as great as smoking and diabetes. But what if there were one component of diet that had huge effect on both heart disease and premature death?

The long chain omega-3 fatty acids (EPA & DHA) might just fill that bill. We already know they significantly reduce the risk of heart disease (see below), but could they also help us live longer? This study (MI McBurney et al, American Journal of Clinical Nutrition, published online June 16, 2021) was designed to answer that question.

Metabolism 101: What Is The Omega-3 Index And Why Is It Important?

Clinical studies on the benefits of omega-3s have been plagued by the question of how to best measure the omega-3 status of the participants.

You can ask the participants to fill out a dietary survey and calculate how many omega-3-rich foods they are eating, but:

- Dietary recall is notoriously inaccurate. People don’t remember everything they ate and have a hard time estimating portion sizes.

You can measure omega-3 fatty acids in the blood, but:

- Blood levels are transient. Omega-3 fatty acids enter the bloodstream from the intestine and then disappear from blood as they are taken up by the cells.

- Different forms of omega-3s (esters versus acetate, for example) are absorbed from the intestine and taken up by cells at different rates.

You can measure the omega-3 content of cellular membranes. This is the best assay for omega-3 status because:

- The long chain omega-3 fatty acids (EPA and DHA) that have the biggest effect on heart disease risk accumulate in our cell membranes.

- Omega-3 fatty acids are essential (our bodies can’t make them). That means the omega-3 content of our cell membranes reflect the omega-3 content of our diet. This is one of the cases where the saying, “We are what we eat”, is literally true.

- The omega-3 content of our cell membranes is relatively stable. It reflects the omega-3 content of our diet over the last few months.

In theory, you could measure the omega-3 content of cell membranes from any tissues in the body, but red blood cells can easily be obtained by a simple blood draw, so they are the tissue of choice.

A group lead by Dr. William H Harris standardized this measurement by creating something called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA in red blood cell membranes.

It turns out that the Omega-3 Index is an excellent indicator of heart disease risk.

An Omega-3 Index of less than 4% is associated with a high risk of heart disease.

An Omega-3 Index of more than 8% is associated with a low risk of heart disease.

But could a low Omega-3 Index also be associated with an increased risk of premature death? This is what the current study was designed to find out.

How Was This Study Done?

The data for this study were obtained from the ongoing Framingham Offspring Heart Study.

To put this statement into perspective, the original Framingham Heart Study began in 1948 in Framingham Massachusetts with the goal of identifying the factors that contributed to heart disease. It was one of the first major studies to identify the role of saturated fats, elevated blood cholesterol, and elevated blood triglycerides on heart disease risk.

The study is continuing today with the second and third generation descendants of the original study participants. It has also been broadened to include other diseases and additional risk factors, such as the Omega-3 Index.

This study selected 2240 participants from the Framingham Offspring study who had no heart disease and also had Omega-3 Index measurements at the beginning of the study. The study then followed them for 11 years. The goal of the study was to compare the Omega-3 Index with the two most potent risk factors for heart disease (smoking and diabetes) in predicting the risk of premature death.

The characteristics of the participants at the beginning of the 11-year study were:

43% male, 57% female.
Average age = 65.
3% were smokers.
8% were diabetic.
Average Omega-3-Index = 5.8%. This is slightly higher than the American average of ~5%.

Is Low Omega-3-Intake As Bad For You As Smoking?

The participants in the study were divided into 5 quintiles based on their Omega-3 Index.

The 20% of the group in the lowest quintile had an Omega-3 Index of <4.2%.

The 20% of the group in the highest quintile had an Omega-3 Index of >6.8%.

First, the scientists running the study did a direct comparison of the top three risk factors on the risk of premature death. Here is what they found.

The group with the lowest average Omega-3 Index died 4.74 years earlier than the group with the highest average Omega-3 Index.

Smokers died 4.73 years earlier than non-smokers.

People with diabetes died 3.90 years earlier than people without diabetes.

That means low omega-3 intake was just as bad for the participants in this study as smoking. Even the authors of the study were surprised by this result. They had expected omega-3 fatty acids to be beneficial, but they had not expected them to be as beneficial as not smoking.

Because omega-3 fatty acid intake and smoking were the two most potent risk factors for premature death, the authors looked at the interaction between the two. They found that the predicted 11-year survival was:

85% for non-smokers with high omega-3 intake.

71% for either…

- Smokers with high omega-3 intake, or…

- Non-smokers with low omega-3 intake.

Only 47% for smokers with low omega-3 intake.

Simply put, this study predicts if you were a 65-year-old smoker with low omega-3 intake, you could almost double your chances of surviving another 11 years by giving up smoking and increasing your omega-3 intake.

In the words of the authors, “Smoking and omega-3 intake seem to be the most easily modified risk factors [for premature death]…Dietary choices that change the Omega-3 index may prolong life.”

The Bottom Line

We know that smoking is deadly, but could low intake of omega-3 fatty acids be just as deadly?

A recent study compared omega-3 intake with the two most potent risk factors (smoking and diabetes) in predicting the risk of premature death. Here is what it found.

The group with the lowest average omega-3 intake died 4.74 years earlier than the group with the highest average omega-3 intake.

Smokers died 4.73 years earlier than non-smokers.

People with diabetes died 3.90 years earlier than people without diabetes.

That means high omega-3 intake was just as beneficial for the participants in this study as not smoking. Even the authors of the study were surprised by this result. They had expected omega-3 fatty acids to be beneficial, but they had not expected them to be as beneficial as not smoking.

85% for non-smokers with high omega-3 intake.

71% for either…

- Smokers with high omega-3 intake, or…

- Non-smokers with low omega-3 intake.

Only 47% for smokers with low omega-3 intake.

In the words of the authors, “Smoking and omega-3 intake seem to be the most easily modified risk factors [for premature death]…Dietary choices that change the Omega-3 index may prolong life.”

For more details about this study, 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.

How Much Omega-3 Should You Take During Pregnancy?

June 22, 2021 by Dr. Steve Chaney

Which Omega-3s Are Beneficial?

Author: Dr. Stephen Chaney

Preterm births (births occurring before 37 weeks) are increasing in this country. Just between 2018 and 2019, the percentage of preterm births increased by 2% to over 10% of all pregnancies. That is a concern because preterm births are associated with an increased risk of:

Visual impairment.
Developmental delays.
Learning difficulties.
Problems with normal development of lungs, eyes, and other organs.

Plus, it is expensive to keep premature babies alive. One recent study estimated that reducing the incidence of preterm births by around 50% could reduce health care costs by $6 billion in the United Stated alone.

Of the 10% preterm births, 2.75% of them are early preterm births (births occurring before 34 weeks). Obviously, the risk of health problems and the cost of keeping them alive is greatest for early preterm babies.

We don’t know why preterm births are increasing, but some experts feel it is because in this country:

More older women are having babies.

There is increased use of fertility drugs, resulting in multiple babies

Unfortunately, there is no medical standard for identifying pregnancies at risk for preterm birth. Nor is there any agreement around prevention measures for preterm births.

However, recent research has suggested that some premature births may be caused by inadequate omega-3 status in the mother and can be prevented by omega-3 supplementation.

What Do We Know About Omega-3s And Risk Of Preterm Births?

The problem is that almost all these claims have been called into question by other studies. If you are pregnant or thinking of becoming pregnant, you don’t know what to believe.

Fortunately, a group called the Cochrane Collaboration has recently reviewed these studies. The Cochrane Collaboration consists of 30,000 volunteer scientific experts from across the globe whose sole mission is to analyze the scientific literature and publish reviews of health claims so that health professionals, patients, and policy makers can make evidence-based choices about health interventions. Their reviews are considered the gold standard of evidence-based medicine.

This is because most published meta-analyses simply report “statistically significant” conclusions. However, statistics can be misleading. As Mark Twain said: “There are lies. There are damn lies. And then there are statistics”.

The problem is the authors of most meta-analyses group studies together without considering the quality of studies included in their analysis. This creates a “Garbage In – Garbage Out” effect. If the quality of individual studies is low, the quality of the meta-analysis will also be low.

The Cochrane Collaboration reviews are different. They also report statistically significant conclusions from their meta-analyses. However, they carefully consider the quality of each individual study in their analysis. They look at possible sources of bias. They look at the design and size of the studies. Finally, they ask whether the conclusions are consistent from one study to the next. They clearly define the quality of evidence that backs up each of their conclusions.

For omega-3s and pregnancy, the Cochrane Collaboration performed a meta-analysis and review of 70 randomized controlled trials that compared the effect of added omega-3s on pregnancy outcomes with the effect of either a placebo or no omega-3s. These trials included almost 19,927 pregnant women.

This Cochrane Collaboration Review looked at all the claims for omega-3s and pregnancy outcome, but they concluded that only two of the claims were supported by high-quality evidence:

Omega-3s reduce the risk of preterm births.

Omega-3s reduce the risk of low birth-weight infants.

The authors concluded: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the risk of preterm birth…More studies comparing [the effect of] omega-3s and placebo [on preterm births] are not needed at this point.”

In other words, they are saying this conclusion is definite. The Cochrane Collaboration has declared that omega-3 supplementation should become part of the standard of medical care for pregnant women.

However, the Cochrane Collaboration did say that further studies were needed “…to establish if, and how, outcomes vary by different types of omega-3s, timing [stage of pregnancy], doses [of omega-3s], or by characteristics of women.”

That’s because these variables were not analyzed in this study. The study included clinical trials:

Of women at low, moderate, and high risk of poor pregnancy outcomes.

With DHA alone, with EPA alone, and with a mixture of both.

Omega-3 doses that were low (˂ 500 mg/day), moderate (500-1,000 mg/day), and high (> 1,000 mg/day).

I have discussed these findings in more detail in a previous issue of “Health Tips From The Professor”

How Was This Study Done?

The current study (SE Carlson et al, EClinicalMedicine, 2021) is a first step towards answering those questions.

The authors of this study focused on how much DHA supplementation is optimal during pregnancy. This is an important question because there is currently great uncertainty about how much DHA is optimal:

The American College of Obstetrics and Gynecology recommends supplementation with 200 mg/day of DHA. However, that recommendation assumes that the increase will come from fish and was influenced by concerns that omega-3-rich fish are highly contaminated with heavy metals and PCBs.

Another group of experts was recently asked to develop guidelines for omega-3 supplementation during pregnancy. They recommended pregnant women consume at least 300 mg/day of DHA and 220 mg/day of EPA.

The WHO has recommended of minimum dose of 1,000 mg of DHA during pregnancy.

Many prenatal supplements now contain 200 mg of DHA, but very few provide more than 200 mg.

Accordingly, the authors took the highest and lowest recommendations for DHA supplementation and asked whether 1,000 mg of DHA per day was more effective than 200 mg of DHA at reducing the risk of early preterm births. Their hypothesis was that 1,000 mg of DHA would be more effective than 200 mg/day at preventing early preterm births.

This study was a multicenter, double-blind, randomized trial of 1032 women recruited at one of three large academic medical centers in the United States (University of Kansa, Ohio State University, and University of Cincinnati).

The women were ≥ 18 years old (average age = 30) and between 12 and 20 weeks of gestation when they entered the study.

The breakdown by ethnicity was 50% White, 22% Black or African American, 22% Hispanic, 6% Other.

18% had a prior preterm birth (<37 weeks) and 7% had a prior early preterm birth (<34 weeks).

Prior to enrollment in the study 47% of the participants reported taking a DHA supplement and 19% of the participants took a DHA supplement with > 200 mg/day.

All the participants received 200 mg DHA capsules and were told to take one capsule daily. The participants were also randomly assigned to take 2 additional capsules that contained a mixture of corn and soybean oil (the 200 mg DHA/day group) or 2 capsules that contained 400 mg of DHA (the 1,000 mg DHA/day group). The capsules were orange flavored so the participants could not distinguish between the DHA capsules and the placebo capsules.

Blood samples were drawn upon entry to the study and either just prior to delivery or the day after delivery to determine maternal DHA status.

The study was designed to look at the effect of DHA dose (1,000 mg or 200 mg) on early preterm birth (<34 weeks), preterm birth (<37 weeks), low birth weight (< 3 pounds), and several other parameters related to maternal and neonatal health.

How Much Omega-3 Should You Take During Pregnancy?

The primary findings from this study were:

The rate of early preterm births (<34 weeks) was less (1.7%) for pregnant women taking 1,000 mg of DHA/day compared to 200 mg/day (2.4%).

The rate of late preterm births (between 34 and 37 weeks) was also less for women taking 1,000 mg of DHA/day compared to 200 mg/day.

Finally, low birth weight and the frequency of several maternal and neonatal complications during pregnancy, delivery, and immediately after delivery were also lower with 1,000 mg/day of supplemental DHA than with 200 mg/day.

This confirms the authors’ hypothesis that supplementation with 1,000 mg/day of DHA is more effective than 200 mg/day at reducing the risk of early preterm births. In addition, this study showed that supplementation with 1,000 mg of DHA/day had additional benefits.

This study did not have a control group receiving no DHA. However:

The US average for early preterm births is 2.74%.

For the women in this study who had previous pregnancies, the rate of early preterm birth was 7%.

Of course, the important question for any study of this type is whether all the women benefited equally from supplementation. Fortunately, this study was designed to answer that question.

As noted above, each woman was asked whether they took any DHA supplements at the time they enrolled in the study, and 47% of the women in the study were taking DHA supplements when they enrolled. In addition, the DHA status of each participant was determined from blood samples taken at the time the women were enrolled in the study. When the authors split the women into groups based on their DHA status at the beginning of the study:

For women with low DHA status the rate of early preterm births was 2.0% at 1,000 mg of DHA/day versus 4.1% at 200 mg of DHA/day.

For women with high DHA status the rate of early preterm births was around 1% for both 1,000 mg of DHA/day and 200 mg of DHA/day.

In other words, DHA supplementation only appeared to help women with low DHA status. This is good news because:

DHA status is an easy to measure predictor of women who are at increased risk of early preterm birth.

This study shows that supplementation with 1,000 mg of DHA/day is effective at reducing the risk of early premature birth for women who are DHA deficient.

In the words of the authors, “Clinicians could consider prescribing 1,000 mg DHA daily during pregnancy to reduce early preterm birth in women with low DHA status if they are able to screen for DHA.”

Which Omega-3s Are Beneficial?

DHA is the most frequently recommended omega-3 supplement during pregnancy.

It is not difficult to understand why that is.

DHA is a major component of the myelin sheath that coats every neuron in the brain. [You can think of the myelin sheath as analogous to the plastic coating on a copper wire that allows it to transmit electricity from one end of the wire to the other.]

Unlike other components of the myelin sheath, the body cannot make DHA. It must be provided by the diet.

During the third trimester, DHA accumulates in the human brain faster than any other fatty acid.

Animal studies show that DHA deficiency during pregnancy interferes with normal brain and eye development.

Some, but not all, human clinical trials show that DHA supplementation during pregnancy improves developmental and cognitive outcomes in the newborn.

Recent studies have shown that most women in the United States only get 60-90 mg/day of DHA in their diet.

Clearly, DHA is important for fetal brain development during pregnancy, and most pregnant women are not getting enough DHA in their diet. This is why most experts recommend supplementation with DHA during pregnancy. And this study suggests supplementation with 1,000 mg/day is better than 200 mg/day. However, two important questions remain:

#1: Is 1,000 mg of DHA/day optimal? The answer is, “We don’t know”. This study compared the highest recommended dose (1,000 mg/day) with the lowest recommended dose (200mg/day) and concluded that 1,000 mg/day was better than 200 mg/day.

But would 500 or 800 mg/day be just as good as 1,000 mg/day? We don’t know. More studies are needed.

#2: Can DHA do it all, or are other omega-3s also important for a healthy pregnancy? As noted above, the emphasis on supplementation with DHA was based on the evidence for a role of DHA in fetal brain development during pregnancy.

But is DHA or EPA more effective at preventing early preterm birth and maternal pregnancy complications? Again, we don’t know.

As noted above, the Cochrane Collaboration concluded that omega-3s were effective at reducing early preterm births but was unable to evaluate the relative effectiveness of EPA and DHA because their review included studies with DHA only, EPA only, and EPA + DHA.

This is an important question because the ability of the body to convert EPA to DHA and vice versa is limited (in the 10-20%) range. This means that if both EPA and DHA are important for a healthy pregnancy, it might not be optimal to supplement with a pure DHA or pure EPA supplement.

Based on currently available data if you are pregnant or thinking of becoming pregnant, my recommendations are:

Chose a supplement that provides both EPA and DHA.

Because the evidence is strongest for DHA at this time, chose an algal source of omega-3s that has more DHA than EPA.

Aim for a dose of DHA in the 500 mg/day to 1,000 mg/day range. Remember, this study showed 1,000 mg/day was better than 200 mg/day but did not test whether 500 or 800 mg/day might have been just as good.

As more data become available, I will update my recommendations.

The Bottom Line

The Cochrane Collaboration recently released a report saying that the evidence was definitive that omega-3 supplementation during pregnancy reduced the risk of early preterm births. However, they were not able to reach a definitive conclusion on the optimal dose of omega-3s or the relative importance of EPA and DHA at preventing early preterm birth.

Most experts recommend that pregnant women supplement with between 200 mg/day and 1,000 mg/day of DHA.

A recent study asked whether 1,000 mg of DHA/day was better than 200 mg/day at reducing the risk of early preterm birth. The study found:

The rate of early preterm births (<34 weeks) was less (1.7%) for pregnant women taking 1,000 mg of DHA/day than pregnant women taking 200 mg/day (2.4%).

For women with low DHA status at the beginning of the study, the rate of early preterm births was 2.0% at 1,000 mg of DHA/day versus 4.1% at 200 mg of DHA/day.

For women with high DHA status at the beginning of the study, the rate of early preterm births was around 1% for both 1,000 mg of DHA/day and 200 mg of DHA/day.

The authors concluded, “Clinicians could consider prescribing 1,000 mg DHA daily during pregnancy to reduce early preterm birth in women with low DHA status…”

There are two important caveats:

This study did not establish the optimal dose of DHA. The study concluded that 1,000 mg/day was better than 200 mg/day. But would 500 or 800 mg/day be just as good as 1,000 mg/day? We don’t know. More studies are needed.

This study did not establish the relative importance of EPA and DHA for reducing the risk of early preterm births. DHA is recommended for pregnant women based on its importance for fetal brain development. But is DHA more important than EPA for reducing the risk of early preterm births? Again, we don’t know. More studies are needed.

For more details about this study and my recommendations, read the article above.

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

Do Omega-3s Add Years To Your Life?

June 1, 2021 by Dr. Steve Chaney

Why Are Omega-3s So Controversial?

Author: Dr. Stephen Chaney

I don’t need to tell you that omega-3s are controversial. Some experts confidently tell you that omega-3s significantly reduce your risk of heart disease and may reduce your risk of cancer and other diseases. Other experts confidently tell you that omega-3s have no effect on heart disease or any other disease. They claim that omega-3 supplements are no better than “snake oil”.

The problem is that each camp of experts can cite published clinical studies to support their claims. How can that be? How can clinical studies come to opposite conclusions on such an important topic? The problem is that it is really difficult to do high quality clinical studies on omega-3s. I will discuss that in the next section.

The question of whether omega-3s affect life span has also been controversial. Heart disease and cancer are the top two causes of death in this country. So, if omega-3s actually reduced the risk of heart disease and cancer, you might expect that they would also help us live longer. Once again, there are studies on both sides of this issue, but they are poor quality studies.

We need more high-quality studies to clear up the controversies surrounding the health benefits of omega-3s. I will report on one such study in this issue of “Health Tips From The Professor”. But first let me go into more depth about why it is so difficult to do high-quality studies with omega-3 fatty acids.

Clinical Studies 101: Why Are Omega-3s So Controversial?

I have covered this topic in previous issues of “Health Tips From the Professor”, but here is a quick summary.

Randomized, placebo controlled clinical trials (RCTs) are considered the gold standard for evidence-based medicine, but they ill-suited to measure the effect of omega-3s on health outcomes.

- Heart disease and cancer take decades to develop. Most RCTs are too small and too short to show a meaningful effect of omega-3s on these diseases.

- To make up for this shortcoming, some recent RCTs have started with older, sicker patients. This way enough patients die during the study that it can measure statistically significant outcomes. However, these patients are already on multiple medications that mimic many of the beneficial effects of omega-3s on heart disease.

These studies are no longer asking whether omega-3s reduce the risk of heart disease. They are really asking if omega-3s have any additional benefits for patients who are already taking multiple medications – with all their side effects. I don’t know about you, but that is not the question I am interested in.

- Until recently, most RCTs did not measure circulating omega-3 levels before and after supplementation, so the investigators had no idea whether omega-3 supplementation increased circulating omega-3 levels by a significant amount.

And for the few studies where omega-3 levels were measured before and after supplementation, it turns out that for many of the participants, their baseline omega-3 levels were too high for omega-3 supplementation to have a meaningful effect. Only participants with low omega-3 levels at the beginning of the study benefited from omega-3 supplementation.

These studies are often quoted as showing omega-3 supplementation doesn’t work. However, they are actually showing the true value of supplementation. Omega-3 supplementation isn’t for everyone. It is for people with poor diet, increased need, genetic predisposition, and/or pre-existing disease not already treated with multiple medications.

2) Prospective cohort studies eliminate many of the shortcomings of RCTs. They can start with a large group of individuals (a cohort) and follow them for many years to see how many of them die or develop a disease during that time (this is the prospective part of a prospective cohort trial). This means they can start with a healthy population that is not on medications.

This also means that these studies can answer the question on most people’s minds, “Are omega-3s associated with reduced risk of dying or developing heart disease?” However, these studies have two limitations.

- They are association studies. They cannot measure cause and effect.

- Ideally, omega-3 levels would be measured at the beginning of the study and at several intervals during the study to see if the participant’s diet had changed during the study. Unfortunately, most prospective cohort studies only measure omega-3 levels at the beginning of the study.

3) Finally, a meta-analysis combines data from multiple clinical studies.

- The strength of a meta-analysis is that the number of participants is quite large. This increases the statistical power and allows it to accurately assess small effects.

- The greatest weakness of meta-analyses is that the design of the individual studies included in the meta-analysis is often quite different. This introduces variations that decrease the reliability of the meta-analysis. It becomes a situation of “Garbage in. Garbage out”

The study (WS Harris et al, Nature Communications, Volume 12, Article number: 2329, 2021) I am discussing today is a meta-analysis of prospective cohort studies. It was designed to determine the association between blood omega-3 fatty acids and the risk of:

Death from all causes.
Death from heart disease.
Death from cancer.
Death from causes other than heart disease or cancer.

More importantly, it eliminated the major weakness of previous meta-analyses by only including studies with a similar design.

How Was This Study Done?

This study was a meta-analysis of 17 prospective cohort studies with a total of 42,466 individuals looking at the association between omega-3 fatty acid levels in the blood and premature death due to all causes, heart disease, cancer, and causes other than heart disease and cancer.

Participants in the 17 studies were followed for an average of 16 years, during which time 15,720 deaths occurred. This was a large enough number of deaths so that a very precise statistical analysis of the data could be performed.

The average age of participants at entry into the studies was 65, and 55% of the participants were women. Whites constituted 87% of the participants, so the results may not be applicable to other ethnic groups. None of the participants had heart disease or cancer when they entered the study.

Finally, the associations were corrected for a long list of variables that could have influenced the outcome (Read the publication for more details).

A strength of this meta-analysis is that all 17 studies were conducted as part of the FORCE (Fatty Acids & Outcomes Research Consortium) collaboration. The FORCE collaboration was established with the goal of understanding the relationships between fatty acids (as measured by blood levels of the omega-3 fatty acids) on premature death and chronic disease outcomes (cardiovascular disease, cancer, and other conditions).

Each study was designed using a standardized protocol, so that the data could be easily pooled for a meta-analysis. In the words of the FORCE collaboration founders:

The larger sample sizes of [meta-analyses] will substantially increase statistical power to investigate associations…enabling the [meta-analyses] to discover important relationships not discernible in any individual study.

2) Standardization of variable definitions and modeling of associations will reduce variation and potential bias in estimates across cohorts.

3) Results will be far less susceptible to publication bias.

Do Omega-3s Add Years To Your Life?

The meta-analysis divided participants into quintiles based on blood omega-3 levels. When comparing participants with the highest omega-3 levels with participants with the lowest omega-3 levels:

Premature death from all causes was decreased by 16%.

- When looking at the effect of individual omega-3s, EPA > EPA+DHA > DHA.

Premature death from heart disease was decreased by 19%.

- When looking at the effect of individual omega-3s, DHA > EPA+DHA > EPA.

Premature death from cancer was decreased by 15%.

- When looking at the effect of individual omega-3s, EPA > DHA > EPA+DHA.

Premature death from causes other than heart disease and cancer was decreased by 18%.

- When looking at the effect of individual omega-3s, EPA > EPA+DHA > DHA.

The differences between the effects of EPA, DHA, and EPA+DHA were small.

ALA, a short chain omega-3 found in plant foods, had no effect on any of these parameters.

In the words of the authors: “These findings suggest that higher circulating levels of long chain omega-3 fatty acids are associated with a lower risk of premature death. Similar relationships were seen for death from heart disease, cancer, and causes other than heart disease and cancer. No associations were seen with the short chain omega-3, ALA [which is found in plant foods]”.

What Does This Study Mean For You?

If you are thinking that 15-19% decreases in premature death from various causes don’t sound like much, let me do some simple calculations for you. The average lifespan in this country is 78 years.

A 16% decrease in death from all causes amounts to an extra 12.5 years. What would you do with an extra 12.5 years?

A 19% decrease in death from heart disease might not only allow you to live longer, but it has the potential to improve your quality of life by living an extra 15 years free of heart disease.

Similarly, a 15% decrease in death from cancer might help you live an extra 12 years cancer-free.

In other words, you may live longer, and you may also live healthier longer, sometimes referred to as “healthspan”.

Don’t misunderstand me. Omega-3s are not a magic wand. They aren’t the fictional “Fountain of Youth”.

There are many other factors that go into a healthy lifestyle. If you sit on your couch all day eating Big Macs and drinking beer, you may be adding the +12.5 years to a baseline of -30 years.

Clinical studies report average values and none of us are average. Omega-3s will help some people more than others.

I will understand if you are skeptical. It seems like every time one study comes along and tells you that omega-3s are beneficial, another study comes along and tells you they are worthless.

This was an extraordinarily well-designed study, but it is unlikely to be the final word in the omega-3 controversy. There are too many poor-quality studies published each year. Until everyone in the field agrees to some common standards like those in the FORCE collaboration, the omega-3 controversy will continue.

The Bottom Line

A recent meta-analysis looked at the association between omega-3 fatty acid levels in the blood and premature death due to all causes, heart disease, cancer, and causes other than heart disease and cancer.

The meta-analysis divided participants into quintiles based on blood omega-3 levels. When comparing participants with the highest omega-3 levels with participants with the lowest omega-3 levels:

Premature death from all causes was decreased by 16%.

Premature death from heart disease was decreased by 19%.

Premature death from cancer was decreased by 15%.

Premature death from causes other than heart disease and cancer was decreased by 18%.

For more details about study 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.