Omega-3s Reduce Preterm Births

Do Omega-3s Make For A Healthy Pregnancy?

Author: Dr. Stephen Chaney 

omega-3s during pregnancy is healthyThe 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?

ghost bustersIt’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?

Clinical StudyFor 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

clinically provenHere 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?

pregnant women taking omega-31) 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

We Have Been Asking The Wrong Questions 

Author: Dr. Stephen Chaney

Confusion Clinical StudiesToday’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 FailureCongestive 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

Omega-3s And Heart DiseaseWhen 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

ScientistAs 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.

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.

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.

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

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

Author: Dr. Stephen Chaney

deadWe 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?

professor owlClinical 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?

Clinical StudyThe 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?

omega-3 supplements and heart healthThe 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.

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.”

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.

What Is An Anti-Inflammatory Diet?

Can Diet Douse The Flames?

Author: Dr. Stephen Chaney

InflammationIf you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It is something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. How good is the evidence that certain foods influence inflammation, and what does an anti-inflammatory diet look like?

The Science Behind Anti-Inflammatory Diets

ScientistLet me start by saying that the science behind anti-inflammatory diets is nowhere near as strong as it is for the effect of primarily plant-based diets on heart disease and diabetes. The studies on anti-inflammatory diets are mostly small, short duration studies. However, the biggest problem is that there is no standard way of measuring inflammation.

There are multiple markers of inflammation, and they do not change together. That means that in every study some markers of inflammation are altered, while others are not. There is no consistent pattern from one study to another.

In spite of these methodological difficulties, the studies generally point in the same direction. Let’s start with the strongest evidence and work our way down to the weakest evidence. 

Omega-3 fats are anti-inflammatory (I. Reinders et al, European Journal of Clinical Nutrition, 66: 736-741, 2011). The evidence is strongest for the long chain omega-3s found in fish and fish oil, but the shorter chain omega-3s found in foods like walnuts, flaxseeds, chia seeds and flaxseed oil, soybean oil, and canola oil also appear to be anti-inflammatory. 

Inflammation is directly correlated with glycemic index (L. Qi and F.B. Lu, Current Opinion in Lipidology, 18: 3-8, 2007). This has a couple of important implications.

The most straightforward is that refined carbohydrates and sugars (sodas, pastries, and desserts), which have a high glycemic index, increase inflammation. In contrast, complex carbohydrates (whole grains, most fruits and vegetables) decrease inflammation. No surprise there. The second implication is that it is the glycemic index, not the sugar, that is driving the inflammatory response.

That means we need to look more closely at foods than at sugars. Sodas, pastries and desserts are likely to cause inflammation, but sugar-containing foods with a low glycemic index are unlikely to be inflammatory. 

Fruits and vegetables are anti-inflammatory. This has been shown in multiple studies. At this point most of the research is centered on identifying the nutrients and phytonutrients from fruits and vegetables that are responsible for the reduction in inflammation. I suspect the investigators are hoping to design an anti-inflammatory supplement and make lots of money. I will stick with the fresh fruits and vegetables. 

Saturated fats are inflammatory. At face value, the data on saturated fats appear to be contradictory. Some Fatty Foodsstudies say that saturated fats increase inflammation, while others say they do not. However, similar to my earlier discussion on saturated fats and heart disease), the outcome of the study depends on what the saturated fats are replaced with.

When saturated fats are replaced with refined carbohydrates, sugar and highly processed foods (the standard American low-fat diet), inflammation doesn’t change. This doesn’t mean that a diet high in saturated fat is healthy. It just means that both diets are bad for you. Both are inflammatory.

However, when saturated fat is replaced with omega-3 polyunsaturated fats (J.A. Paniagua et al, Atherosclerosis, 218: 443-450, 2011) or monounsaturated fats (B. Vessby et al, Diabetologia, 44: 312-319, 2001), markers of inflammation decrease. Clearly, saturated fats are not the best fat choice if you wish to keep inflammation in check.

I would be remiss if I did not address the claims by the low-carb diet proponents that saturated fats do not increase inflammation in the context of a low-carb diet. I want to remind you of two things we have discussed previously:

  • The comparisons in those studies are generally with people consuming a diet high in simple carbohydrates and sugars.
  • These studies have mostly been done in the short-term when the participants are losing weight on the low-carb diets. Weight loss decreases inflammation, so the reduction in inflammation on the low-carb diet could be coming from the weight loss.

The one study (M. Miller et al, Journal of the American Dietetic Association, 109: 713-717, 2009) I have found that compares a low-carb diet (the Atkins diet) with a good diet (the Ornish diet, which is a low-fat, lacto-ovo vegetarian diet) during weight maintenance found that the meat based, low-carb Atkins diet caused greater inflammation than the healthy low-fat Ornish diet.

Red meat is probably pro-inflammatory. Most, but not all, studies suggest that red meat consumption is associated with increased inflammation. If it is pro-inflammatory, the inflammation is most likely associated with its saturated fat, its heme iron content, or the advanced glycation end products formed during cooking.

What Is An Anti-Inflammatory Diet?

Colorful fruits and vegetablesAnti-inflammatory diets have become so mainstream that they now appear on many reputable health organization websites such as Harvard Health, WebMD, the Mayo Clinic, and the Cleveland Clinic. Each have slightly different features, but there is a tremendous amount of agreement. 

Foods an anti-inflammatory diet includes: In a nutshell, an anti-inflammatory diet includes fruits and vegetables, whole grains, plant-based proteins (like beans and nuts), fatty fish, and fresh herbs and spices. Specifically, your diet should emphasize:

  • Colorful fruits and vegetables. Not only do they help fight inflammation, but they are a great source of antioxidants and other nutrients important for your health.
  • Whole grains. They have a low glycemic index. They are also a good source of fiber, and fiber helps flush inflammatory toxins out of the body.
  • Beans and other legumes. They should be your primary source of protein. They are high in fiber and contain antioxidants and other anti-inflammatory nutrients.
  • Nuts, olive oil, and avocados. They are good sources of healthy monounsaturated fats, which fight inflammation.
  • Fatty fish. Salmon, tuna, and sardines are all great sources of long chain omega-3 fatty acids, which are fish and fish oilincorporated into our cell membranes. Those long chain omega-3s in cell membranes are, in turn, used to create compounds that are powerful inflammation fighters.

Walnuts, flaxseeds, and chia seeds are good sources of short chain omega-3s. The efficiency of their conversion to long chain omega-3s that can be incorporated into cell membranes is only around 2-5%. If they fight inflammation, it is probably because they replace some of the saturated fats and omega-6 fats you might otherwise be eating.

  • Herbs and spices. They add antioxidants and other phytonutrients that fight inflammation.

Foods an anti-inflammatory diet excludes: In a nutshell, an anti-inflammatory diet should exclude highly processed, overly greasy, or super sweet foods, especially sodas and other sweet drinks. Specifically, your diet should exclude:

  • Refined carbohydrates, sodas and sugary foods. They have a high glycemic index, which is associated with inflammation. They can also lead to weight gain and high blood sugar, both of which cause inflammation.
  • Foods high in saturated fats. This includes fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats. This includes margarine, coffee creamers, and any processed food containing partly hydrogenated vegetable oils. Trans fats are very pro-inflammatory.
  • French fries, fried chicken, and other fried foods. They used to be fried in saturated fat and/or trans fat. Nowadays, they are generally fried in omega-6 vegetable oils. A little omega-6 in the diet is OK, but Americans get too much omega-6 fatty acids in their diet. Most studies show that a high ratio of omega-6 to omega-3 fatty acids is pro-inflammatory.
  • Foods you are allergic or sensitive to. Eating any food that you are sensitive to can cause inflammation. This comes up most often with respect to gluten and dairy because so many people are sensitive to one or both. However, if you are not sensitive to them, there is no reason to exclude whole grain gluten-containing foods or low-fat dairy foods from your diet.

Can Diet Douse The Flames?

FlamesIn case you didn’t notice, the recommendations for an anti-inflammatory diet closely match the other healthy diets I have discussed previously. It should come as no surprise then that both the Mediterranean (L. Gallard, Nutrition in Clinical Practice, 25: 634-640, 2010; L. Schwingshackl and G. Hoffmann, Nutrition Metabolism and Cardiovascular Diseases, 24: 929-939, 2014) and DASH (D.E. King et al, Archives of Internal Medicine, 167: 502-506, 2007) diets are anti-inflammatory.

Vegan and vegetarian diets also appear to be anti-inflammatory as well. The anti-inflammatory nature of these diets undoubtedly contributes to their association with a lower risk of heart disease, diabetes, and cancer.

As for the low-carb diets, the jury is out. There are no long-term studies to support the claims of low-carb proponents that their diets reduce inflammation. The few long-term studies that are available suggest that low-carb diets are only likely to be anti-inflammatory if vegetable proteins and oils replace the animal proteins and fats that are currently recommended.

What does this mean for you if you have severe arthritis or other inflammatory diseases? An anti-inflammatory diet is unlikely to “cure” your symptoms by itself. However, it should definitely be a companion to everything else you are doing to reduce inflammation.

The Bottom Line 

If you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It’s something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. In this article I review the evidence that certain foods influence inflammation and describe what an anti-inflammatory diet looks like.

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.

Update On Omega-3 Supplementation And Heart Disease

How Much Omega-3s Do You Need?

Pendulum
Pendulum

In previous issues of “Health Tips From The Professor” I have described the medical consensus about omega-3 supplementation and heart disease as resembling a pendulum.

A few positive studies are published, and the pendulum swings in the positive direction. The medical consensus becomes, “Omega-3s may reduce heart disease risk.”

Then a few negative studies are published, and the pendulum swings in the other direction. The consensus becomes that omega-3 supplements are worthless. One review a few years ago went so far as to say that fish oil supplements were the modern-day version of snake oil.

Meta-analyses combine the data from multiple clinical studies to increase statistic power and minimize the effect of clinical studies that are outliers. They are supposed to provide clear answers to medical questions like the effect of omega-3 supplements on heart disease.

However, the meta-analyses published to date have also reached conflicting conclusions about the effectiveness of omega-3 supplementation. No wonder you [and the medical community] are confused!

In 2018 three large, well-designed, clinical studies looking at the effect of omega-3 supplementation on heart disease risk were published. They reached different conclusions. However, they covered a much wider range of omega-3 doses than previous studies. And the studies with the highest doses of omega-3s showed the most positive effect of omega-3 supplementation on the reduction of heart disease risk.

That lead a group of doctors and scientists from the United States and Finland to postulate that many previous studies had failed to find an effect of omega-3 supplements on heart disease risk because the dose of omega-3s they used was too low.

These scientists designed a very large meta-analysis (AA Bernasconi et al, Mayo Clinic Proceedings, doi.org/10.1016/j.mayocp.2020.08.034) to test their hypothesis. In short, their study was designed to:

  • Determine whether supplementation with the omega-3 fatty acids EPA and DHA resulted in reduced heart disease risk.
  • Quantify the relationship between the dose of EPA + DHA and the risk of heart disease outcomes.

How Was The Study Done?

Clinical StudyThis study was a meta-analysis of 40 randomized control clinical studies on the effect omega-3 supplementation on heart disease outcomes. Specifically:

  • It included all high-quality clinical studies of omega-3 supplementation published before August 2019.
  • It included a total of 135,267 participants.
  • It included participants at both low and high risk of developing heart disease.
  • It included studies of supplementation with EPA alone and with EPA + DHA.
  • It included omega-3 doses ranging from 400 mg/day to 5,500 mg/day.
  • It excluded dietary studies because:
    • It is difficult to measure the dosage of omega-3s that participants are consuming in dietary studies.
    • It is difficult to assure their compliance with dietary advice.
    • There is variation in the omega-3 content of various foods.
    • Participants in these studies are often advised to make other changes in diet. It then becomes difficult to know whether any benefits observed were from changes in omega-3s or from changes in other components of the diet.

Update On Omega-3 Supplementation And Heart Disease

omega-3 supplements and heart healthHere are the results of the meta-analysis. Supplementation with EPA or EPA + DHA reduced:

  • Coronary Heart disease (defined as diseases caused by atherosclerosis, such as angina, heart attack, and heart failure) by 10%.
  • Heart Attacks by 13%.
  • Coronary Heart disease deaths by 9%.
  • Heart attack deaths by 35%.

Because of the large number of participants in this meta-analysis, they were able to reach some other important conclusions:

  • Despite the claims you may have heard about a new drug consisting of highly purified EPA, this study found no evidence that EPA supplementation was superior to EPA + DHA supplementation.
  • Even though heart medications provide some of the same benefits as omega-3s, this study concluded that omega-3 supplementation reduced the risk of heart disease even for patients on multiple heart medications.
  • This study also concluded that omega-3 supplementation was likely to be effective for people at both low and high risk of heart disease. This means that omega-3 supplementation is likely to be beneficial for preventing heart disease.

The authors concluded: “The current study provides strong evidence that EPA + DHA supplementation is an effective strategy for the prevention of certain coronary heart disease outcomes…Considering the relatively low costs and side effect profiles of omega-3 supplementation and the low drug-drug interactions with other standard therapies…clinicians and patients should consider the potential benefits of omega-3 (EPA/DHA) supplementation…”

What Does This Study Mean For You?

Heart AttackThe most significant conclusions from this study are the reduction in heart attacks and heart attack deaths. That is because:

  • Approximately 1.5 million Americans suffer a heart attack each year. For those who survive their quality of life may be permanently altered.
    • A 13% reduction in heart attacks means that something as simple as EPA + DHA supplementation might prevent as many as 195,000 heart attacks a year.
  • Approximately 100,000 Americans will die from a heart attack each you.
    • A 35% reduction in heart attack deaths means that EPA + DHA supplementation might prevent as many as 35,000 deaths from heart attacks each year.
  • For many Americans sudden death from a heart attack is the first indication that they have heart disease.
    • As Benjamin Franklin said, “An ounce of prevention is worth a pound of cure”. That is why EPA + DHA supplementation makes sense for most people.

I can’t say that this study will be the final word on omega-3 supplementation and heart disease risk. However, several recent studies have supported the benefit of omega-3 supplementation at reducing heart disease risk. The pendulum has clearly swung in the direction of omega-3s being beneficial for heart health.

Of course, omega-3 supplementation is not a magic “Get Out of Jail Free” card. You can’t expect it to overcome the effects of a bad diet and lack of exercise with omega-3 supplementation alone. You need a holistic approach.

The American Heart Association recommends:

Doctor With Patient

  • If you smoke, stop.
  • Choose good nutrition.
    • Choose a diet that emphasizes vegetables, fruits, whole grains, low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils, and nuts.
    • Choose a diet that limits sweets, sugar-sweetened beverages, and red meats.
  • Reduce high blood cholesterol and triglycerides.
  • Reduce your intake of saturated fat, trans fat and cholesterol and get moving.
  • Lower High Blood Pressure.
  • Be physically active every day.
    • Aim for at least 150 minutes per week of moderate-intensity physical activity per week.
  • Aim for a healthy weight.
  • Manage diabetes.
  • Reduce stress.
  • Limit alcohol.
  • Have a regular physical checkup.

Add in omega-3 supplementation to these recommendations and you have a winning combination.

How Much Omega-3s Do You Need?

Question MarkAs I mentioned at the beginning of this article the omega-3 dosages used in the studies included in this meta-analysis ranged from 400 mg/day to 5,500 mg/day. More importantly, there were enough participants in these studies to obtain a fairly accurate estimate of dose response. This allow the authors to answer the question, “How much omega-3s do I need?”The study found that:

  • The protective effect of omega-3s for heart attack deaths and coronary heart disease deaths plateaued with dosages of EPA + DHA that exceeded 800 – 1200 mg/day.
  • The dose response of the protective effect of omega-3s for non-fatal heart attacks was linear over a wider range of dosages, with every increase 1,000 mg/day of EPA + DHA decreasing the risk of heart attack by 9%.

Based on the totality of their data, the authors concluded, “…clinicians and patients should consider the potential benefits of omega-3 supplementation, especially using 1,000 to 2,000 mg/day dosages, which are rarely obtained in most Westernized diets, even those including routine fish consumption.”

The Bottom Line

A recent meta-analysis combined the data from 40 clinical studies with over 135,000 participants looking at the effect of omega-3 supplementation on various types of heart disease. The study found that supplementation with EPA or EPA + DHA reduced:

  • Coronary Heart disease (defined as diseases caused by atherosclerosis, such as angina, heart attack, and heart failure) by 10%.
  • Heart Attacks by 13%.
  • Coronary Heart disease deaths by 9%.
  • Heart attack deaths by 35%.

Because of the large number of participants in this meta-analysis, they were able to reach some other important conclusions:

  • This study found no evidence that EPA supplementation was superior to EPA + DHA supplementation.
  • This study concluded that omega-3 supplementation reduced the risk of heart disease even for patients on multiple heart medications.
  • This study also concluded that omega-3 supplementation was likely to be effective for people at both low and high risk of heart disease. This means that omega-3 supplementation is likely to be beneficial for preventing heart disease.
  • The optimal dose of EPA + DHA appeared to be 1,000 – 2,000 mg/day.

The authors of the study concluded: “The current study provides strong evidence that EPA + DHA supplementation is an effective strategy for the prevention of certain coronary heart disease outcomes…Considering the relatively low costs and side effect profiles of omega-3 supplementation and the low drug-drug interactions with other standard therapies…clinicians and patients should consider the potential benefits of omega-3 (EPA/DHA) supplementation, especially using 1,000 to 2,000 mg/day dosages, which are rarely obtained in most Westernized diets, even those including routine fish consumption.”

For more details, including a more detailed discussion of what this study means for you, read the article above.

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

Do Omega-3 Supplements Reduce ADHD Symptoms?

Will The Omega-3 Controversy Continue?

adhd symptoms childrenThe prevalence of ADHD has increased dramatically in the last couple of decades. One study reported that the percentage of children diagnosed with ADHD has increased by 42% between 2003 and 2011. Another study reported an increase of 67% between 1997 and 2015. Currently, 10-12% of American schoolchildren are diagnosed with ADHD. That amounts to around 6 million children with ADHD, at a cost to taxpayers of over $45 billion.

An estimated 65% of children with ADHD are taking medications to control their symptoms. Unfortunately, those medications don’t work for 20-40% of patients with ADHD. Even worse, ADHD medications come with serious side effects like loss of appetite and delayed growth, sleep disorders, nausea & stomach pains, headaches, moodiness and irritability.

Even more worrisome is that many children say they “just don’t feel right” while they are on the drugs. Finally, there is the unintended message we are sending our children that drugs are the solution to their problems.

It is no wonder that millions of parents are looking for more natural solutions for their child’s ADHD. One of the most popular natural approaches is supplementation with omega-3s. But do omega-3 supplements work, or is this just another myth created by supplement companies to lighten your wallet?

The scientific evidence is conflicting. Some clinical studies support the efficacy of omega-3 supplements for reducing ADHD symptoms. Other studies claim they have no benefit.

In today’s issue of “Health Tips From The Professor”, I review a recent meta-analysis (JP-C Chang et al, Neuropsychopharmacology, 43: 534-545, 2018) that attempts to provide a definitive answer to this question.

How Was The Study Done?

Clinical StudyThis study was designed to answer three questions:

1)    Does omega-3 supplementation reduce ADHD symptoms?

2)    Does omega-3 supplementation improve cognitive skills in children with ADHD?

3)    Is there an association between omega-3 status and ADHD?

Previous meta-analyses on these topics had design flaws such as:

·       Including both children and adult subjects.

·       Including subjects with diagnosis other than ADHD.

·       Including trials that supplemented with vitamins and other nutrients in addition to omega-3s.

The authors of this study tried to avoid these limitations by using the following criteria for the studies that were included in their meta-analysis.

1)    The studies were randomized, double-blind, placebo-controlled trials of omega-3 supplementation with DHA and EPA alone or in combination.

2)    The participants were school-aged children (4-12 years) and adolescents (13-17 years) who had a diagnosis of ADHD.

3)    The study measured the effect of omega-3 supplementation on clinical symptoms of ADHD or measures of cognitive performance (omission errors, commission errors, forward memory, backward memory, and information processing).

4)    The studies were large enough to measure statistically significant differences.

5)    The studies were published in peer-reviewed journals.

With these criteria there were:

·       Seven studies with 534 children looking at the effect of omega-3 supplementation on ADHD symptoms.

·       Three studies with 214 children looking at the effect of omega-3 supplementation on cognitive performance.

·       Twenty studies with 1276 children looking at the association between omega-3 status and ADHD.

Do Omega-3 Supplements Reduce ADHD Symptoms?

adhd symptoms omega-3sThe results of this meta-analysis were as follows:

1)    Omega-3 supplementation significantly reduced ADHD symptoms reported by parents.

2)    Omega-3 supplementation significantly improved cognitive measures associated with attention span (omission and commission errors). [Note: Omission errors consist of leaving important information out of an answer. Commission errors consist of including incorrect information in an answer.]

·       Omega-3 supplementation did not improve cognitive measures associated with memory and information processing. This has also been reported in most previous studies.

·       The best way to think of this is that children with ADHD are fully capable of learning their schoolwork. However, they may have trouble demonstrating what they have learned on exams because of omission and commission errors.

·       In this context, omega-3 supplementation may help them perform better on exams and reduce test-taking anxiety.

3)    For hyperactivity, only studies with EPA dosages of 500 mg per day or greater showed a significant reduction in symptoms.

4)    Children diagnosed with ADHD have lower levels of DHA, EPA, and total omega-3s.

The authors concluded: “In summary, there is evidence that omega-3 supplementation … improves clinical symptoms and cognitive performances in children and adolescents with ADHD, and that these youth have a deficiency in omega-3 levels. Our findings provide further support to the rationale for using omega-3s as a treatment option for ADHD.”

They also said: “Our paper shows that EPA supplementation dosage >500 mg should be considered when treating youth with ADHD, especially those with predominantly hyperactivity/impulsivity presentation.”

Will The Omega-3 Controversy Continue?

ArgumentThis is an excellent study, but it is unlikely to be the final word on this subject. That is because there is a fundamental flaw in all previous studies on this important subject, including the ones included in this meta-analysis.

In the words of the authors: “In terms of ‘personalized medicine’, it is tempting to speculate that a subpopulation of youth with ADHD and low levels of omega-3s may respond better to omega-3 supplementation, but there are no studies to date attempting this approach.”

Until studies of omega-3 supplementation and ADHD symptoms include measures of omega-3 status before and after supplementation, those studies are likely to continue giving conflicting results. That is because:

·       If most of the children in the study have low omega-3 status, we are likely to see a positive effect of omega-3 supplementation on ADHD symptoms.

·       If most of the children in the study have high omega-3 status, we are likely to see a negative effect of omega-3 supplementation on ADHD symptoms.

What Does This Study Mean For You?

confusionWhile this study is unlikely to end the omega-3 controversy, it is a very well-designed study that combines the results of multiple double-blind, placebo-controlled clinical trials. In short, it is a very strong study.

Omega-3s have no side effects and multiple health benefits. If your child suffers from ADHD, omega-3 supplementation is worth a try.

However, we need to keep omega-3 supplementation in perspective:

·       Not every child with ADHD will respond to omega-3 supplementation.

·       Omega-3s alone are likely to reduce, but not eliminate, the symptoms.

·       There are other natural approaches that should be considered.

You will find details on omega-3s and other natural approaches for reducing ADHD symptoms in an earlier issue of “Health Tips From The Professor”.

The Bottom Line

A recent meta-analysis looked at the effect of omega-3 supplementatation on ADHD symptoms. Here is a brief summary of the data:

1)    Omega-3 supplementation significantly reduced ADHD symptoms reported by parents.

2)    Omega-3 supplementation significantly improved cognitive measures associated with attention span (omission and commission errors). [Note: Omission errors consist of leaving important information out of an answer. Commission errors consist of including incorrect information in an answer.]

·       Omega-3 supplementation did not improve cognitive measures associated with memory and information processing. This has also been reported in most previous studies.

·       The best way to think of this is that children with ADHD are fully capable of learning their schoolwork. However, they may have trouble demonstrating what they have learned on exams because of omission and commission errors.

·       In this context, omega-3 supplementation may help them perform better on exams and reduce test-taking anxiety.

3)    For hyperactivity, only studies with EPA dosages of 500 mg per day or greater showed a significant reduction in symptoms.

4)    Children diagnosed with ADHD have lower levels of DHA, EPA, and total omega-3s.

The authors concluded: “In summary, there is evidence that omega-3 supplementation … improves clinical symptoms and cognitive performances in children and adolescents with ADHD, and that these youth have a deficiency in omega-3 levels. Our findings provide further support to the rationale for using omega-3s as a treatment option for ADHD.”

They also said: “Our paper shows that EPA supplementation dosage >500 mg should be considered when treating youth with ADHD, especially those with predominantly hyperactivity/impulsivity presentation.”

For more details on the study and a perspective on omega-3 supplementation compared to other natural approaches for reducing ADHD symptoms, read the article above.

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

Can Fish Oil Make Children Smarter?

When Do Omega-3 Supplements Make Sense?

Author: Dr. Stephen Chaney

Confused ChildWe know that the omega-3 fatty acids found in fish oil are critically important for brain development. But will they really help our kids learn better? Some studies suggest that they do, while other studies have come up empty. Why is this? More importantly, what does it mean for your children? Will fish oil supplements help or not?

I’ve selected today’s study (Portillo-Reyes et al, Research in Developmental Disabilities, 35: 861-870, 2014) because it sheds some light on those important questions.

Can Fish Oil Make Children Smarter?

This study looked at the effect of supplementation for 3 months with 360 mg of EPA + DHA on cognitive function of malnourished Mexican children, ages 8-12 years old. The children came from poor neighborhoods where foods rich in omega-3 fatty acids were seldom available. Low intake of omega-3 fatty acids was confirmed by a food frequency survey.

Cognition was assessed based on a battery of 16 standardized cognition tests at the beginning of the study and again 3 months later.

The results were fairly clear cut. The children receiving the fish oil supplements showed significant gains in mental processing speed, visual-motor coordination, perceptual integration, attention span and executive function compared to children receiving a placebo. In case you were wondering, the first three most strongly affect a child’s ability to learn and last two affect their tendency to display ADHD symptoms.

What Is the Significance of This Study?

There are a lot of things not to like about the study:

  • It was a small study (59 children total)
  • Blood levels of omega-3 fatty acids were not determined.
  • It was a short term study (12 months would have been better).
  • Measuring the ability to learn is difficult. Experts in the field differ about which cognitive tests are best. I’m not taking a position on the adequacy of the tests they were using because that is not my area of expertise.
  • Because it was done in a poor region of Mexico, one could argue that its applicability to children in this country is uncertain.

 

So why even mention this study? That’s because it illustrates an important principle – one that is often ignored in the design and interpretation of clinical studies.

Simply put, the principle is that not everyone will benefit equally from supplementation. It is the malnourished and the sick who will benefit most. When you focus your clinical studies on those groups you are most likely to observe a benefit of supplementation. When you focus your study on well nourished, healthy individuals it will be much more difficult to observe any benefit. And if you perform a meta-analysis of all studies, without evaluating the studies on the basis of need – nutrition status and health status – benefits will also be much more difficult to demonstrate.

This study is just one example of that principle. In an earlier “Health Tips From the Professor” (Can DHA Help Johnny Read?) I reported on a study looking at the effect of DHA supplementation on reading ability of English schoolchildren. In that study, it was the children who were most deficient in DHA and started with the lowest reading skills who benefitted most from DHA supplementation.

What does all of this mean to you?

  • If you are a parent, you may be asking if a study done with Mexican children eating poor diets has any relevance for your kids. In today’s world of pop tarts and pizza it just might. Most children don’t order sardines on their pizza. As a consequence, many American children don’t get enough omega-3 fatty acids in their diet.
  • Should your children be getting more omega-3s in their diet? A recent study concluded that most American children only get 20-40 mg/day of DHA from their diet. So if your child’s food preferences don’t include salmon, sardines and the like – and if your child is experiencing learning issues or problems with ADHD, you might consider adding fish oil supplements to their diet. There’s no need to megadose. The international standard is around 200 mg/day of DHA for children 7 or older.
  • If you are one of those people who is confused by conflicting headlines about the benefits of supplementation, you may want to look at the studies behind those headlines and ask if supplementation would have been likely to provide any benefit in the subjects studied.

The Bottom Line:

1)     A recent study reported that supplementation with fish oil significantly improved learning skills in children consuming a diet that was deficient in omega-3 fatty acids.

2)     If your children are not consuming foods rich in omega-3 fatty acids such as coldwater fish, you might wish to make sure that they are getting adequate levels of omega-3 fatty acids in their diet. Most experts recommend around 200 mg/day for children over 7.

3)     This study also illustrates the principle that supplementation is most likely to be of demonstrable benefit to those who have the worst diets and the greatest need. That doesn’t mean that supplementation won’t benefit everyone, but it does mean that it may be difficult to prove the value of supplementation in healthy people consuming a good diet.

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 Lower Blood Pressure?

The Good News About Fish Oil

Author: Dr. Stephen Chaney

High Blood PressureHigh blood pressure or hypertension is a major problem in this country. Over 60% of Americans have high blood pressure. Only 47% of those with hypertension are adequately controlled. 20% of them don’t even know that they have high blood pressure.

In this case, ignorance is definitely not bliss. That’s because high blood pressure significantly increases the risk of stroke, heart attacks and congestive heart failure.

The causes of high blood pressure are many. Genetics, obesity, lack of exercise, sodium, alcohol, saturated fats and too few fresh fruits and vegetables all play a role. Age also plays a role. As we age, our blood vessels become less flexible and our blood pressure rises by about 0.6 mm Hg per year.

Medications can help, but many of them have significant side effects and often aren’t fully effective in controlling blood pressure. That’s why natural approaches are so important.

Because there are so many causes of hypertension, natural approaches for lowering your blood pressure are not simple. Natural approaches start with weight loss, restricting sodium intake, increasing physical activity, moderating alcohol intake and something called the DASH diet. In short, there is not just one simple change that you can make that will totally eliminate hypertension. It requires a complete lifestyle change.

That’s why the latest study on the effect of omega-3s on blood pressure is so exciting. If the headlines are true, adding omega-3s to your diet may be one of the most effective things you can do to lower your blood pressure naturally. So let’s examine the study to see if the headlines are accurate.

How Was The Study Designed?

This study (Miller et al, American Journal of Hypertension, doi:10.1093/ajh/hpu024) was a very large, well designed study. It is a meta-analysis of 70 randomized, placebo controlled clinical studies. Key characteristics of these studies were:

  • The mean study duration was 69 days. That means these beneficial effects occur relatively quickly.
  • The mean EPA + DHA dose was 3.8 g/day (range = 0.2 – 15 g/day). A wide range of doses was included.
  • The EPA & DHA came from all sources (seafood, EPA+DHA fortified foods, fish oil, algal oil, and purified ethyl esters. The source did not affect the outcome.
  • Olive oil was the most commonly used placebo, with omega-6 vegetable oils being used as placebos in a few studies. The choice of placebo did not affect the outcome.
  • None of the people in these studies were taking blood pressure lowering medications. That means these studies were specifically designed to see whether omega-3s lowered blood pressure, not whether they had any additional benefit for people already taking medications. This is important because if you only focus on groups who are already taking multiple medications, you tend to obscure the beneficial effects of omega-3s (see my recent Health Tip “Is Fish Oil Really Snake Oil?”)

Do Omega-3s lower Blood Pressure?

Fish OilThe authors of the study reported that:

  • Compared to placebo, EPA+DHA reduced systolic blood pressure (that’s the upper reading) by 1.52 mm Hg and diastolic blood pressure (that’s the lower reading) by 0.99 mm Hg.
  • When they looked at those participants who already had high blood pressure, the numbers were even more impressive – a 4.51 mm Hg decrease in systolic blood pressure and a 3.05 mm Hg decrease in diastolic blood pressure. That’s important because for each 2 mm Hg reduction in blood pressure there is a 6% decrease in stroke mortality, a 4% decrease in heart disease mortality, and a 3% decrease in total mortality.

More to the point, the authors of the study concluded that “A decrease of 4.51 mm Hg in systolic blood pressure among those with high blood pressure could help an individual avoid having to take medication to control blood pressure levels”.

  • When they looked at the study participants who had normal blood pressure the numbers were still significant – a 1.25 mm Hg decrease in systolic blood pressure and a 0.62 decrease in diastolic blood pressure. The authors pointed out that this could prevent, or at least delay, the age-related progression towards hypertension.
  • The effect of omega-3s on systolic blood pressure (4.51 mm Hg decrease) was comparable to the most successful lifestyle interventions – 3-10 mm Hg decrease for 10 pound weight loss, 4-9 mm Hg decrease for increased physical activity, 2-8 mm Hg decrease for sodium restriction, and 2-4 mm Hg for decreased alcohol consumption.
  • A dose of at least 1 gm/day of EPA+DHA was required for a significant decrease in systolic blood pressure, and a dose of over 2 gm/day was required for a significant decrease in both systolic and diastolic blood pressure

While this is a single study, it is consistent with a number of previous studies in this area. Based on the existing body of literature I would recommend omega-3s as part of a holistic approach for keeping your blood pressure under control.

The Bottom Line:

1)     A recent meta-analysis of 70 published clinical studies (AJH, doi: 10.1093/ajh/hpu024) has shown fairly convincingly that omega-3 fatty acids are effective at lowering blood pressure. Moreover, this study is consistent with a number of previous studies. The evidence appears to be strong enough for omega-3s to be considered as part of a holistic approach to keeping your blood pressure under control.

2)     If you already have high blood pressure, you should know that omega-3s caused blood pressure to decrease by 4.51 mm Hg in people like you. The authors of the study concluded that this decrease in blood pressure is large enough that some people may be able to avoid blood pressure medicines entirely. For others addition of omega-3s to their diet will likely allow their physicians to reduce the dose of medications required to keep their blood pressure under control – thus minimizing the side effects of the medications.

3)     If you already have slightly elevated blood pressure that has not yet progressed to clinical hypertension, you should know that omega-3s also give a modest decrease in blood pressure in people like you. The authors of the study concluded that this decrease was enough to prevent or delay the age-related onset of hypertension.

4)     The effect of omega-3s on reducing blood pressure is equivalent to the most successful lifestyle changes (weight loss, increased physical activity, sodium restriction and alcohol moderation). That doesn’t mean that you should pop fish oil pills and forget the other lifestyle changes. The idea is to combine as many of those lifestyle changes as possible so that you may never have to worry about high blood pressure again.

5)     You need at least 1 gm/day of EPA+DHA to reduce systolic blood pressure and more than 2 gm/day to reduce both systolic and diastolic blood pressure.

6)     Contrary to the hype you may have been reading elsewhere, the source of EPA+DHA didn’t matter. The only caveat is that many people really struggle with trying to get 1-2 gm/day of EPA+DHA from fish. It’s a bit too much of a good thing.

7)     Don’t think of hypertension as a “Do it yourself” project. Hypertension is a silent killer. It’s one of those diseases where the first symptom is often sudden death – or, even worse, a life that is no longer worth living. Work with your physician. Let them help you find the right balance between lifestyle changes (including omega-3s) and medications to keep your blood pressure under control.

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.

Are Saturated Fats Good For You?

Is Everything We Thought We Knew About Fats Wrong?

Author: Dr. Stephen Chaney

fatty steakBring out the fatted calf! Headlines are proclaiming that saturated fats don’t increase your risk of heart disease – and that they may actually be good for you.

The study (Annals of Internal Medicine, 160: 398-406, 2014) that attracted all the attention in the press was what we scientists call a meta-analysis. Basically, that is a study that combines the data from many clinical trials to improve the statistical power of the effect being studied.

And it was a very large study. It included 81 clinical trials that looked at the effects of various types of fat on heart disease risk.

Are Saturated Fats Good For You?

The answer to this question is a simple No. The headlines suggesting that saturated fats might be good for you were clearly misleading. The study concluded that saturated fats might not increase the risk of heart disease, but it never said that saturated fats were good for you.

In short, the study concluded that:

  • Saturated fats, monounsaturated fats and long-chain omega-6 polyunsaturated fats did not affect heart disease risk.
  • Long chain omega-3 polyunsaturated fats decreased heart disease risk [Note: The original version of the paper said that the decrease was non-significant, which is what the headlines have reported. However, after several experts pointed out an error in their analysis of the omega-3 data, the authors corrected their analysis, and the corrected data show that the decrease in risk is significant.]
  • Trans fats increased heart disease risk

If those conclusions are correct, they would represent a major paradigm shift. We have been told for years that we should limit saturated fats and replace them with unsaturated fats. Has that advice been wrong?

Is Everything We Thought We Knew About Fats Wrong?

Before we bring out the fatted calf and start heaping butter on our12 ounce steaks, perhaps we should look at some of the limitations of this study.

We Eat Foods, Not Fats

When the authors broke the data down into the effects of individual saturated and unsaturated fatty acids on heart disease risk some interesting insights emerge.

For example, with respect to saturated fats:

  • Both palmitic acid and stearic acid – which are abundant in palm oil and animal fats – increased the risk of heart disease.
  • On the other hand, margic acid – which is more abundant in dairy products – decreased the risk of heart disease.

Whipped CreamSo while the net effect of saturated fats on heart disease risk may be zero, these data suggest:

  • It is still a good idea to avoid fatty meats, especially red meats, if you want to reduce your risk of heart disease. When you focus on foods, rather than fats this fundamental advice has not changed in over 40 years! In next week’s “Health Tips From the Professor” I will share some of the latest research on the dangers of red meat.
  • With fatty dairy foods the situation is a little more uncertain. I’m not ready to tell you to break out the butter and whipped cream just yet, but recent research does suggest that dairy foods have some beneficial effects that may outweigh their saturated fat content.

With respect to omega-3 fatty acids:

  • alpha-linolenic acid – which is found in vegetable oils and nuts and is the most abundant omega-3 fatty acids in our diets – had no effect on heart disease risk.
  • On the other hand, EPA and DHA – which are found primarily in oily fish and omega-3 supplements – decreased heart disease risk by 20-25%.

Once again, while the net effect of omega-3 fatty acids on heart disease risk was very small, that’s primarily because most Americans consume mostly alpha-linolenic acid and very little EPA and DHA. This study shows that fish oil significantly reduces heart disease risk, which is fully consistent with the heart healthy advice of the American Heart Association and National Institutes of Health over the past decade or more.

What We Replace the Fats With Is Important

A major weakness of the current study is that it did not ask what the individual clinical trials were replacing the fatty acids with. Many of them were simply replacing the saturated fats with carbohydrates. To understand why that is important, you have to go back to the research of Dr. Ancel Keys.

The whole concept of saturated fats increasing the risk of heart disease is based on the groundbreaking research of Dr. Ancel Keys in the 50’s and 60’s. But, it is important to understand what his research showed and didn’t show.

His research showed that when you replaced saturated fats with monounsaturated fats and/or polyunsaturated fats the risk of heart disease was significantly reduced. He was the very first advocate of what we now call the Mediterranean diet. (He lived to 101 and his wife lived to 97, so he must have been on to something.)

Unfortunately, his diet advice got corrupted. The mantra became low fat diets, where the saturated fat was replaced with carbohydrates – mostly simple sugars and refined flours. Since diets containing a lot of simple sugars and refined flours also increase the risk of heart disease you completely offset the benefits of getting rid of the saturated fats.

Just in case you think that is outdated dietary advice, Dr. Key’s recommendations were confirmed by a major meta-analysis published in 2009 (American Journal of Clinical Nutrition, 89: 1425-1432, 2009). That study showed once again that replacing saturated fats with carbohydrates had no effect on heart disease risk, while replacing them with polyunsaturated fats significantly reduced risk.

The Bottom Line:

You can put the fatted calf back out to pasture. The headlines telling you that saturated fats don’t increase the risk of heart disease were overstated and misleading. This study does not represent a paradigm shift. In fact, when you analyze the study in depth it simply reaffirms much of the current dietary advice about fats.

1)     When you simply replace saturated fats with carbohydrates, as did many of the studies in the meta-analysis that generated all of the headlines, there is little or no effect on heart disease risk. However, other studies have shown that when you replace the saturated fats with monounsaturated and polyunsaturated fats you significantly reduce heart disease risk.

In short, if you are interested in reducing your risk of heart disease, low fat diets may be of relatively little value while Mediterranean diets may be beneficial. No paradigm shift there. That sounds pretty familiar.

2)     Fatty meats, especially red meats, appear to increase the risk of heart disease. No surprises there.

3)     Alpha-linolenic acid, the short chain omega-3 fatty acid found in nuts, seeds and vegetable oils, does not decrease heart disease risk. However, EPA and DHA, the long chain omega-3 fatty acids found in fatty fish and fish oil supplements significantly decrease heart disease risk. That’s probably because the efficiency of conversion of alpha-linolenic acid to EPA & DHA in our bodies is only around 10%. No surprises there.

4)     The study did suggest that dairy foods may decrease heart disease risk. While there are a few other studies supporting that idea, I’m not ready to break out the butter and whipped cream yet. More research is needed.

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 Fish Oil Really Snake Oil?

Does Fish Oil Reduce Heart Disease Risk?

Author: Dr. Stephen Chaney

Fish OilOne of my readers recently sent me a video titled “Is Fish Oil Just Snake Oil?” and asked me to comment on it. The doctor who made the video claimed that the most recent studies had definitively shown that omega-3 fatty acids, whether from fish or fish oil, do not decrease the risk of heart attack, stroke or cardiovascular death. He went on to say that the case was closed. There was no point in even doing any more studies.

My reader, like many of you, was confused. Wasn’t it just a few years ago we were being told that clinical studies have shown that omega-3 fatty acids significantly reduce the risk of heart disease? Hadn’t major health organizations recommended omega-3 fatty acids as part of a heart health diet? What has changed?

The answer to the first two questions is a resounding YES, and “What has changed?” is THE story.  Let me explain.

Fish Oil And Heart Disease Risk In Healthy People

If we look at intervention studies in healthy people (what we scientists refer to as primary prevention studies) the results have been pretty uniform over the years. In a primary prevention setting, fish oil cannot be shown to significantly reduce the risk of heart disease (Rizos et al, JAMA, 308: 1024-1033, 2012).

That’s not unexpected because it is almost impossible to show that any intervention significantly reduces the risk of heart disease in healthy populations. For example, as I pointed out in recent Health Tips From the Professor (“Do Statins Really Work?” and “Can An Apple A Day Keep Statins Away?”) you can’t even show that statins significantly reduce heart attack risk in healthy populations.

If you can’t prove that statins reduce the risk of heart attacks in a healthy population, it should come as no surprise that you can’t prove that fish oil reduce heart attacks in a healthy population. To answer that question we need to look at whether fish oil reduces the risk of heart attacks in high risk populations.

Fish Oil And Heart Disease Risk In Sick People – The Early Studies

Most of the early  studies looking at the effect of fish oil in patients at high risk of cardiovascular disease (what we scientists refer to as secondary prevention studies) reported very positive results.

For example, the DART1 study (Burr et al, Lancet, 2: 757-761, 1989) and the US Physician’s Health Study (Albert et al, JAMA, 279: 23-28, 1998) reported a 29% decrease in total mortality and a 52% decrease in sudden deaths related to heart disease in patients consuming diets rich in omega-3 containing fish.

Even more striking was the GISSI-Prevenzione study (Marchioli et al, Lancet, 354: 447-455, 1999; Marchioli et al, Eur. Heart J, 21: 949-952, 2000; Marchioli et al, Circulation, 105: 1897-1903, 2002). This was a very robust and well designed study. It looked at the effect of a fish oil supplement providing 1 g/day of omega-3 fatty acids on the risk of a second heart attack in 11,323 patients who had survived a non-fatal heart attack within the last 3 months – a very high risk group.

The results were clear cut. Over the next 3.5 years supplementation with fish oil reduced overall death by 15% and sudden death due to heart disease by 30% compared to a placebo. And, if you looked at the first 4 months, when the risk of a second heart attack is highest, the fish oil supplement reduced the risk of overall death by 41% and sudden death by 53%.

The authors estimated that treating 1,000 heart attack patients with 1 g/day of fish oil would save 5.7 lives per year. That is almost identical to the 5.2 lives saved per 1,000 patients per year by the statin drug pravastatin in the LIPID trial (NEJM, 339: 1349-1357, 1998).

No wonder the American Heart Association said that patients “could consider fish oil supplementation for heart disease risk prevention.”

Fish Oil And Heart Disease Risk In Sick People – The Latest Studies

Heart Health StudyHowever, the most recent studies have been uniformly negative. For example, the ORIGIN trial (Bosch et al, NEJM, 367: 309-318, 2012) treated 12,536 patients who were considered at high risk of heart disease because of diabetes or pre-diabetes with either 1 g/day of fish oil or a placebo. This was also a robust, well designed study, and it found no effect of the fish oil supplement on either heart attacks or deaths due to heart disease.

Similarly, a recent meta-analysis looking at the combined effects of 14 randomized, double-blind, placebo-controlled trials in patients at high risk of heart disease found no significant effect of fish oil supplements on overall deaths, sudden death due to heart disease, heart attacks, congestive heart failure or stroke (Kwak et al, Arch. Int. Med., 172: 686-694, 2012).

No wonder you are confused by all of the conflicting studies. You must be wondering: “Is the American Heart Association wrong?” “Are fish oil supplements useless for reducing heart disease risk?”

What Has Changed Between The Early Studies & The Latest Studies?

When a trained scientist sees the outcome of well designed clinical studies change over time, he or she asks: “What has changed in the studies?” It turns out that a lot has changed.

1)     In the first place the criteria for people considered at risk for heart attack and stoke have changed dramatically. Not only has the definition of high cholesterol” been dramatically lowered, but cardiologists now treat people for heart disease if they have inflammation, elevated triglycerides, elevated blood pressure, diabetes, pre-diabetes or minor arrythmia.

For example, the GISSI-Prevenzione study recruited patients who had a heart attack within the past three months, while the ORIGIN study just looked at people who had diabetes or impaired blood sugar control. While both groups could be considered high risk, the patients in the earlier studies were at much higher risk for an imminent heart attack or stroke – thus making it much easier to detect a beneficial effect of omega-3 supplementation.

2)     Secondly, the standard of care for people considered at risk for heart disease has also changed dramatically. In the earlier studies patients were generally treated with one or two drugs – generally a beta-blockers and/or drug to lower blood pressure. In the more recent studies the patients generally receive at least 3 to 5 different medications – medications to lower cholesterol, lower blood pressure, lower triglycerides, reduce inflammation, reduce arrhythmia, reduce blood clotting, and medications to reduce the side effects of those medications.

Since those medications perform many of the beneficial effects of omega-3 fatty acids, it is perhaps no surprise that it is now very difficult to show any additional benefit of omega-3 fatty acids in patients on multiple medications.

The bottom line is that we are no longer asking the same question. The earlier studies were asking whether fish oil supplements reduce the risk of heart attacks or cardiovascular death in patients at high risk of heart disease. The more recent studies are asking whether fish oil supplements provide any additional benefits in a high risk population that is already on 3-5 medications to reduce their risk of heart disease.

However, the people who are writing the headlines you are reading (and the videos you are watching) are not making that distinction. They are pretending that nothing has changed in the way the studies are designed. They are telling you that the latest studies contradict the earlier studies when, in fact, they are measuring two different things.

Is Fish Oil Really Snake Oil?

Was the doctor who made the video “Is Fish Oil Just Snake Oil?” correct in saying that omega-3 fatty acids are ineffective at reducing the risk of heart disease? The answer is yes and no.

If you take the medical viewpoint that the proper way to treat anyone at the slightest risk of heart disease is with 3-5 medications – with all of their side effects, the answer seems to be pretty clear cut that adding fish oil to your regimen provides little additional benefit.

However, that is not the question that interests me. I’d like to know whether I can reduce my risk of heart attack and cardiovascular death by taking omega-3 fatty acids in place of those drugs – as the original studies have shown.

I’m sure many of my readers feel the same way.

The Bottom Line

  • Studies performed prior to 2000 have generally shown that fish oil supplements reduce the risk of a second heart attack in patients who have previously had a heart attack. One study even suggested that they were as effective as statin drugs at reducing heart attack risk in this population.
  • Recent studies have called into question the beneficial effects of fish oil supplements at reducing the risk of heart disease. However, these studies were performed with lower risk patients and the patients were on 3-5 medications to reduce their risk of heart attack or stroke.
  • The recent studies are no longer evaluating whether fish oil supplements can reduce the risk of heart disease. They are asking whether they have any additional beneficial effects for people taking multiple medications. That’s a totally different question.
  • So ignore the headlines saying that fish oil is snake oil. If you are content taking multiple medications to reduce your risk of heart disease, it is probably correct to say that omega-3 fatty acids provide little additional benefit.
  • However, if you are interested in a more holistic, drug-free approach to reducing your risk of heart disease, I still recommend omega-3 fatty acids as part of a heart healthy diet, as does the American Heart Association.

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

Health Tips From The Professor