Should You Take an Omega-3 Supplement?


The answer to this question is becoming clearer thanks to new research.

About 10% of American adults take an omega-3 supplement regularly, although they are not sure whether these products actually live up to their health claims. Two new studies published in November 2018 shed light on who could – and who likely – not – benefit from omega-3 supplements.


The first study was the Vitamin D and Omega-3 (VITAL) study, a large, multi-year study of 25,871 healthy adults with no history of cardiovascular disease (heart or blood vessel disease) and a “usual risk” for it. The group was racially diverse and was chosen to be representative of the general population, says the study’s lead author, Dr. JoAnn E. Manson, Professor of Medicine, and Michael and Lee Bell, Professor of Women’s Health at Harvard Medical School.

The researchers tested, among other things, whether a moderate dosage (1 gram per day) of an omega-3 supplement compared to a placebo can help prevent serious cardiovascular events. Cardiovascular events included not only heart attacks, but also stroke and angioplasty procedures to clear blocked arteries.

“The results are a bit complex and nuanced. It’s not a simple yes or no or one-size-fits-all answer. Some groups tended to benefit, others didn’t,” says Dr. Manson.

Although a 1-gram daily omega-3 supplement didn’t significantly reduce major cardiovascular events overall, there was a 28% reduction in heart attacks and promising signals for other heart-related endpoints, she says. While the supplement didn’t seem to protect most healthy people from future heart problems, it appeared to benefit certain groups, especially people who ate less than 1.5 servings of fish per week or ate no fish at all. “These people saw a significant 19% reduction in the primary endpoint of major cardiovascular events and a 40% reduction in myocardial infarction,” said Dr. Manson.

The supplements also appeared to benefit African-American participants, who saw a 77% reduction in heart attacks in those who took the omega-3 supplement compared to those who took the placebo, says Dr. Manson. It is unclear why this group benefited more, and additional studies are needed to confirm the finding.


The second study, called the Reduction of Cardiovascular Events with EPA Intervention Study (REDUCE-IT), included more than 8,000 middle-aged and older adults who had elevated triglyceride levels and had already had a cardiovascular event or other significant risk factors for one. The goal was to find out whether a high-dose, high-dose, 4-gram omega-3 drug, compared to a placebo, could protect participants from future cardiovascular events. This study, led by Dr. Deepak Bhatt, a cardiologist and professor of medicine at Harvard Medical School, found a significant reduction in the risk of dying from heart disease or suffering from a cardiovascular event by 25% in people who took the medication who took the placebo.

High doses of omega-3 supplements like the high-dose omega-3 product used in this study are not for everyone because they pose risks like bleeding or an increase in an abnormal heart rhythm called atrial fibrillation, says Dr. Manson. “Although high doses are associated with some risk, the overall benefits of the high-dose omega-3 product used in the study appear to outweigh the risks for people with high triglyceride levels and a history of or at high risk of cardiovascular disease Disease, “says Dr. Manson.

Choosing the Right Supplement

Are you looking for an over-the-counter omega-3 supplement? Here’s what to look for:

  • A 1 gram dose, unless your doctor recommends more.

  • A combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Each of these fatty acids offer different health benefits.

  • A quality addition. Good quality indicators are sealss from US Pharmacopeia, NSF International, or

If your triglyceride levels are abnormally high and you are at an increased risk of cardiovascular disease, talk to your doctor about whether a high-dose omega-3 prescription might be an option.

Put the results into practice

What do these results mean for you?

People in good health. If you’re healthy and have low or moderate risk of heart disease, you probably won’t need an omega-3 supplement provided you eat fish frequently, says Dr. Manson. You should eat at least two servings of oily fish a week, such as salmon, tuna, or herring. Target fish that are rich in two different omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), each of which offers unique health benefits.

Getting your omega-3s from food is always preferable to dietary supplements. Not only are you getting the marine omega-3s from fish, but you’re also potentially replacing less healthy foods in your diet, like red meat, processed foods, or refined grains, says Dr. Manson. “It’s a good lifestyle change and has been a recommendation for a while. Nothing in these studies replaces a moderate fish intake recommendation,” she says.

Non-fish eaters and African Americans. However, if you can’t eat fish or if you don’t like fish, consider an omega-3 supplement. (Algae-based dietary supplements are an option if you are a vegetarian or a fish allergy sufferer.) African Americans might also consider a dietary supplement based on the unique benefits revealed in this study.

For these two groups, a 1 gram daily supplement might strike a good balance between safety and effectiveness. “Talk to your doctor about whether you are a candidate for a supplement,” says Dr. Manson.

Are you already taking omega-3 fatty acids? If you’re already taking an over-the-counter omega-3 supplement, there is no need to stop taking it if you don’t fall into one of the above categories unless your doctor tells you to. However, if you’re not taking an omega-3 supplement, whether you should start depends on your individual risk factors, says Dr. Manson.

Regardless of whether you choose an omega-3 supplement, you should always strive for a healthy diet and lifestyle. “No dietary supplement is a substitute. We already know that, and I think this is an important point that needs reinforcing,” says Dr. Manson. “Healthy lifestyle habits, including regular physical activity, eating healthy, and not smoking, reduce your risk of heart disease by nearly 80%, and that’s really the top heart health recommendation,” she says.

Cardiovascular risk factors. If you have high triglyceride levels and a history of cardiovascular disease, or have high risk factors for them, a high-dose omega-3 drug may be advisable. This also applies if you are already taking a statin drug. The omega-3 drug does not replace the statin.

Fast facts on the two attempts

The vitamin D and omega-3 study (VITAL)

This study was published online on November 10, 2018 by the New England Journal of Medicine.

Funding source: The US National Institutes of Health.

WHO: 25,871 healthy, racially different people, including 12,786 men aged 50 and over and 13,085 women aged 55 and over.

What: A 1 gram daily prescription omega-3 supplement that contains a combination of two omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). A 1 gram dose was chosen because it is a moderate amount and is unlikely to cause side effects. A control group took a placebo.

The central theses:

  • Omega-3 supplements are unlikely to benefit people who eat at least 1.5 servings of fish per week.

  • Omega-3 supplements can benefit people with low fish consumption or people of African American heritage.

Reducing Cardiovascular Events with an EPA Interventional Study (REDUCE-IT)

This study was published online on November 10, 2018 by the New England Journal of Medicine.

Funding source: Amarin, Inc., the company that makes the prescription drugs used in the study.

WHO: 8,179 middle-aged men and women who have had high triglyceride levels and risk factors for heart disease, or who have had a heart attack, stroke, or cardiovascular event. Risk factors included conditions such as high blood pressure and diabetes. Everyone in the study took a statin to lower high cholesterol.

What: A high-dose, 4-gram daily prescription omega-3 drug or a placebo. Unlike over-the-counter omega-3 fatty acids, the drug only contained EPA.

The central theses: This drug can help protect those at high risk from cardiovascular events. Those who took it died 25% less from heart disease or had a heart attack, stroke, or a type of chest pain called angina. They were also less likely to need a procedure to open a blocked cardiac artery. If you have high triglyceride levels and have had a heart attack or stroke, or have risk factors for cardiovascular disease, you can benefit from taking the high-dose omega-3 product.

Stay tuned

While these two studies revealed some new insights into the potential benefits of omega-3 supplements, more information is likely to become available in the near future. VITAL also examined the effects of omega-3 supplementation on cognitive decline, diabetes, depression and autoimmune diseases. These results will be published next year, says Dr. Manson.

Image: © RomarioIen / Getty Images

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