Omega-3 Fatty Acids Don’t Protect Against Heart Disease?

Do an Internet search on “omega-3 fatty acids” and you’ll find that omega-3s, as they are called, are a type of polyunsaturated fat. They’re a minor component of cell membranes and they have effects in blood clotting. And since your body doesn’t make them, some omega-3s in your diet are considered essential to good health. Eating fatty fish (such as sardines or salmon), nuts, or certain plant oils (canola or soybean oil) occasionally should be sufficient.

Dig a little deeper and you’ll undoubtedly read that omega-3s protect against heart disease and stroke. That claim has spawned a huge omega-3 supplements industry, which encourages you to take an omega-3 supplement pill every day to ward off heart disease. This claim is often backed by at least one research study to support the claim. But is it true?

A recent meta-analysis* of the role of various fats in cardiovascular disease questions the cardiovascular protective effect of omega-3s. To understand why this particular analysis is so important, you need to know what a “meta-analysis” is. Basically, a meta-analysis is a study of many previous studies. In a meta-analysis, each previous study is a single data point. That makes meta-analysis an exceedingly powerful tool to tease out small effects, when one paper may say one thing and another says something quite different.

This particular meta-analysis examined 72 previous research studies, involving over 500,000 people overall. Some of the studies were observational, meaning that they examined the relationship between measured specific fatty acid biomarkers and heart disease risk. Others studies were randomized, controlled experiments of fatty acid supplementation. Overall, there was not a statistically lower risk of cardiovascular disease among participants in the high omega-3 groups, in either kind of study.

Bottom line: You probably get enough of the minimum amounts of omega-3s required for good health in your normal diet. I, for one, won’t be taking an omega-3 pill every day just to avoid heart disease. (For those of you will still choose to take omega-3s “just to be sure”, rest easy; there was no evidence presented in this meta-study that they harm you, either.)

* The complete manuscript is only available by subscription.