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Omega-3 supplements are taken by millions around the world. They are touted as a boost to ensure better health as well as longevity.  These claims have been subject to scrutiny as consumption grows. Research studies continue to shed light on how important omega-3 supplements are, or not.

Firstly what is omega-3?

Before we look at the studies, let’s take a look at omega-3. Without getting too much into the chemical definition, omega-3 fatty acids are naturally unsaturated fats. The body is incapable of making these fatty acids. Thus you will need to either consume foods that contain omega-3 gatty acids or take it in a supplement form.

The main types of omega 3 fatty acids are; alpha­linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).  ALA is normally found in fats from plant foods, such as nuts and seeds (walnuts and rapeseed are rich sources). EPA and DHA are collectively called long chain omega 3 fats. They are naturally found in fatty fish, such as salmon and fish oils including cod liver oil.

The Federal Government’s Dietary Guidelines for Americans 2015–2020 recommends that adults eat 8 or more ounces of a variety of seafood (fish or shellfish) per week for the total package of nutrients seafood provides. They also suggest some seafood choices with higher amounts of EPA and DHA be included. Smaller amounts of seafood are recommended for young children.

When it comes to supplementation, in general health organizations suggest a minimum daily recommendation of 250 mg for DHA and EHA and 1100 for ALA.

Given that globally many make poor food choices,  omega-3 supplements have become substitutes for better eating habits.  Consumers hope that by taking these supplements, they will protect their hearts, skin and even their brain health and just ensure better longevity.

We took a look at three more recent studies to see whether the scientific community’s view of omega-3 supplementation had altered over time.

Cochrane health study challenges omega-3 supplements

Evidence published back in July 2018 showed that omega 3 supplements have little or no effect on improving our risk of experiencing heart disease, stroke or death.

The study published by the  Cochrane Library, combined the results of seventy-nine randomised trials involving 112,059 people. These studies assessed effects of consuming additional omega 3 fat, compared to usual or lower omega 3, on diseases of the heart and circulation. Twenty-five studies were assessed as highly trustworthy because they were well designed and conducted.

The studies

The studies recruited men and women, some healthy and others with existing illnesses from North America, Europe, Australia and Asia. Participants were randomly assigned to increase their omega 3 fats or to maintain their usual intake of fat for at least a year. Most studies investigated the impact of giving a long-chain omega 3 supplement in a capsule form and compared it to a dummy pill.  Only a few assessed whole fish intake. Most ALA trials added omega 3 fats to foods such as margarine and gave these enriched foods, or naturally ALA-rich foods such as walnuts, to people in the intervention groups. And usual (non-enriched) foods to other participants.

Heart health and omega-3

The Cochrane researchers found that increasing long-chain omega 3 provides little if any benefit on most outcomes that they looked at. They found high certainty evidence that long-chain omega 3 fats had little or no meaningful effect on the risk of death from any cause. The risk of death from any cause was 8.8% in people who had increased their intake of omega 3 fats, compared with 9% in people in the control groups.

They also found that taking longer-chain omega 3 fats (including EPA and DHA), primarily through supplements, probably makes little or no difference to the risk of cardiovascular events.  Coronary heart deaths, coronary heart disease events, strokes or heart irregularities.

They reported, however, that long-chain omega 3 fats probably did reduce some blood fats, triglycerides and HDL cholesterol. Reducing triglycerides is likely to be protective of heart disease. However, reducing HDL has the opposite effect.

What effect?

The systematic review suggests that eating more ALA through food or supplements probably has little or no effect on cardiovascular deaths or deaths from any cause.

However, eating more ALA probably reduces the risk of heart irregularities from 3.3 to 2.6%. The review team found that reductions in cardiovascular events with ALA were so small that about 1000 people would need to increase consumption of ALA for one of them to benefit. Similar results were found for cardiovascular death. They did not find enough data from the studies to be able to measure the risk of bleeding or blood clots from using ALA.

 Body Weight and Fatness

The study also assessed whether increasing long-chain omega 3 or ALA  affected body weight or “fatness.”  However, they found no real impact.

Cochrane lead author, Dr. Lee Hooper from the University of East Anglia, UK said: “We can be confident in the findings of this review which go against the popular belief that long-chain omega 3 supplements protect the heart. This large systematic review included information from many thousands of people over long periods.  Despite all this information, we don’t see protective effects.

“The review provides good evidence that taking long-chain omega 3 (fish oil, EPA or DHA) supplements does not benefit heart health or reduce our risk of stroke or death from any cause.  The most trustworthy studies consistently showed little or no effect of long-chain omega 3 fats on cardiovascular health. On the other hand, while oily fish is a healthy food, it is unclear from the small number of trials whether eating more oily fish is protective of our hearts.

walnuts and omega-3| Longevity Live

Plant oil and nuts, yes?

“This systematic review did find however moderate evidence that ALA, found in plant oils (such as rapeseed or canola oil) and nuts (particularly walnuts) may be slightly protective of some diseases of the heart and circulation. However, the effect is very small. 143 people needing to increase their ALA intake to prevent one person developing arrhythmia. One thousand people would need to increase their ALA intake to prevent one person dying of coronary heart disease or experiencing a cardiovascular event.  ALA is an essential fatty acid, an important part of a balanced diet. Increasing intake may be slightly beneficial for prevention or treatment of cardiovascular disease.”

VITAL study on omega 3 supplements

Then there is the VITAL study which was a Vitamin D and Omega-3 Trial. The study was led  by Dr. JoAnn E. Manson, professor of medicine and the Michael and Lee Bell Professor of Women’s Health at Harvard Medical School.

This was a large multi-year study of 25,871 healthy adults. They had no history of cardiovascular (heart or blood vessel–related) disease and were at “usual risk” for it. The group was racially diverse and chosen to be representative of the general population.

According to Harvard Medical Review, researchers tested, among other things, whether a moderate dosage (1 gram a day) of an omega-3 supplement could help prevent major cardiovascular events, compared with a placebo.

No one size fits all

Cardiovascular events included not only heart attacks, but strokes, and angioplasty to clear blocked arteries.

Their findings differed from the Cochrane study, although there were some common themes.

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

healthy with omega-3 supplements

Does supplementation protect healthy people?

The researchers looked at whether or not supplementation was needed for people who already had a healthy diet.  They said, although a daily 1-gram omega-3 supplement did not significantly reduce major cardiovascular events over all, there was a 28% reduction in heart attacks and promising signals for other heart-related endpoints.

While the supplement didn’t seem to protect most healthy people against future heart problems, certain groups did appear to benefit. This is true, particularly of people who eat less than 1.5 servings of fish a week or don’t eat fish at all. “For these people, there was a significant 19% reduction in the primary endpoint of major cardiovascular events, with a 40% reduction in heart attacks,” says Dr. Manson.

African american participants benefit from omega-3 supplementation

The supplements also appeared to benefit African American participants. In fact, they saw a 77% reduction in heart attack for those receiving the omega-3 supplement, compared with those taking the placebo, says Dr. Manson. “It’s unclear why the group benefited more. Additional studies are needed to confirm the findings.”

Key findings of the VITAL study

The findings of this study suggest:

  • Omega-3 supplements likely won’t benefit people who eat at least 1.5 servings of fish per week.
  • However, the study supports the idea that omega-3 supplements may benefit people with low fish consumption or those with African American heritage.


Another study called the Reduction of Cardiovascular Events with EPA–Intervention Trial (REDUCE-IT) looked specifically at high dose omega-3 medication. The study included more than 8,000 middle-aged and older adults. They had elevated triglyceride levels. These men also had already experienced a cardiovascular event or had other significant risk factors for one.

It aimed to find out if daily high-dose, 4-gram prescription omega-3 medication could protect participants against future cardiovascular events, compared with a placebo. The trial was led by Dr. Deepak Bhatt, a cardiologist and professor of medicine at Harvard Medical School.

This study found a substantial 25% reduction in the risk of dying from heart disease or suffering a cardiovascular event, among people who took the medication, compared with those who had the placebo.

Omega-3 supplements may not be appropriate for everyone

Yet Dr. Manson says high doses of omega-3 supplements, like the high-dose omega-3 product used in this trial, aren’t appropriate for everyone. This is because they pose risks, such as bleeding or an increase in a type of abnormal heart rhythm known as atrial fibrillation,  “while high doses are associated with some risk, the overall benefits of the high-dose omega-3 product used in the trial appear to outweigh the risks for people with high triglyceride levels and a history of, or at high risk of, cardiovascular disease.”

Key findings of the REDUCE-IT Study

Key findings suggest:

  • Prescription omega-3 medication medications may help to protect high-risk individuals from cardiovascular events. Those taking it were 25% less likely to die from heart disease or to have 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 heart artery.
  • If you have a high triglyceride level and have had a heart attack or stroke or have risk factors for cardiovascular disease, you might benefit from taking the high-dose omega-3 product.

What do other studies say about the effectiveness of omega-3 supplements? 

Extensive research has been done over time on omega-3s.  Especially the types found in seafood (fish and shellfish) and fish oil supplements. Here is a summary of these findings:

  • Research indicates that omega-3 supplements don’t reduce the risk of heart disease. However, people who eat seafood one to four times a week are less likely to die of heart disease.
  • High doses of omega-3s can reduce levels of triglycerides.
  • Omega-3 supplements may help relieve symptoms of rheumatoid arthritis.
  • Omega-3 supplements have not been convincingly shown to slow the progression of the eye disease’s age-related macular degeneration.
  • For most other conditions for which omega-3 supplements have been studied, the evidence is inconclusive.

Common theme

The common theme is that if you are healthy and are eating enough of the right fish, then you do not need to take an omega-3 supplement.

Dr. Manson suggests that we should all eat at least two servings a week of fatty fish, such as salmon, tuna, or herring. “Aim for fish that are high in two different omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Each of these provides unique health benefits.”

Eat foods rich in omega-3 fatty acids

salmon and omega-3 supplements | Longevity LIVE

Getting your omega-3 fatty acids from food is always preferable to taking a supplement. Not only do you get marine omega-3 fatty acids from fish, but you also potentially replace less healthy foods in your diet. This includes red meat, processed foods, or refined grains.

Dr. Manson suggests: “It’s a good lifestyle change to make and has been a recommendation for a while. Nothing in these studies supersedes the recommendation for moderate fish intake,” she says.

Non-Fish Eaters

However, if you can’t eat fish or don’t like fish, then an omega-3 supplement is something to consider. (Algae-based supplements are an option if you are a vegetarian or allergic to fish.) African Americans might also consider a supplement because of the unique benefits revealed in the REDUCE-IT trial.

For these two groups, a daily 1-gram supplement could provide a good balance between safety and efficacy. “Talk to your health care provider about whether you’re a candidate for a supplement,” says Dr. Manson.

Already taking omega-3s? If you’re already taking an over-the-counter omega-3 supplement, you don’t necessarily need to stop taking it if you don’t fall into one of the categories above, unless your doctor tells you to. But if you’re not taking an omega-3 supplement, whether you should really start depends on your individual risk factors, says Dr. Manson.

How to choose the right omega-3 supplements?

The reality is, most of us are going to buy an omega-3 supplement rather than try and get it from our food sources. But what should we look for  in an over-the-counter omega-3 supplement?

  • A 1-gram dose, unless your doctor recommends more.
  • A combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Each of these fatty acids provides different health benefits.
  • A quality supplement. Good quality indicators include seals from U.S. Pharmacopeia, NSF International, or

If your triglyceride levels are abnormally high and you have an elevated risk for cardiovascular disease, talk to your doctor. You should discuss with a specialist whether a high-dose omega-3 prescription might be an option.

Safety of omega-3 supplements?

  • Omega-3s usually produce only mild side effects, if any.
  • If you’re taking medicine that affects blood clotting or if you’re allergic to fish or shellfish, consult your health care provider before taking omega-3 supplements.

Bottom line

These studies suggest that there are those of us who simply do not need  supplements.  And regardless of whether you opt for omega-3 supplements, you should always strive to maintain a healthy diet and lifestyle.

“No dietary supplement is a substitute. We already know that, and I think this is an important point to reinforce,” says Dr. Manson. “Healthy lifestyle practices, including regular physical activity, healthy diet, and not smoking, will reduce heart disease risk by close to 80%, and that’s really the main recommendation for heart health,” she says.


  1. New Cochrane health evidence challenges belief that omega 3 supplements reduce risk of heart disease, stroke or death:
  2. National Center for Complementary and Integrative Health: Omega-3 Supplements: In Depth.
  3. Harvard Medical School:

Want to improve your mood. Then eat some healthy food. You will  enjoy reading healthy foods for every mood.


Gisèle Wertheim Aymes

Gisèle is the owner of the Longevity brand and a self-proclaimed health hedonist. When she is not working, you'll find in her in a yoga class or active in the great outdoors. Gisèle is passionate about health and sharing information. You can follow her @giselewaymes on Twitter and Instagram or read her Linked-In profile for full bio details.

The content in this editorial is for general information only and is not intended to provide medical or other professional advice. For more information on your medical condition and treatment options, speak to your healthcare professional.