Debunking Myths on Omega-3s

Debunking Myths on Omega-3s

This post was sponsored by the Global Organization for EPA and DHA Omega-3s (GOED). All thoughts are my own.

When it comes to nutrition, it’s tough to differentiate between myths versus facts. This is especially true when it comes to omega-3s. Between the media hype and water cooler discussions with friends or family, many of the statements surrounding omega-3s are actually myths. Here are some I hear most often.

Myth #1: Plant-based omega-3s are the same as omega-3s from fish

In order to understand why this is a myth, it is important to understand the types of omega-3s and the forms they can be found in food. There are three main omega-3s – ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). The best way to think of these is that ALA is found in land-based sources, whereas EPA and DHA come from the sea, or marine-based sources. Foods that contain ALA include chia and flax, whereas EPA and DHA are found in fatty fish such as salmon and mackerel, and also in certain sea algae (which is the only purely vegetarian source of EPA and DHA omega-3s).

EPA and DHA are the primary omega-3s known for supporting heart, brain and eye health at all stages of life, and especially in the prenatal and early childhood years. Interestingly, your brain and retinas of the eyes contain the highest amounts of omega-3s compared to other parts of your body.

So what about ALA? It has health benefits, too, but not to the same extent or degree as EPA and DHA. Also, most people tend to get enough ALA omega-3s, and, while the body is technically able to convert ALA  to EPA and DHA, the rate of conversion is extremely low. Only about 1 to 5-percent of ALA is converted to EPA and DHA, so it is a very inefficient process. It’s best to get EPA and DHA directly from fish or supplements.

If you choose to follow a vegetarian or vegan diet, your best bet it to take an omega-3 supplement made from marine algae, which contain high levels of EPA and DHA. These supplements can be found at your local grocery and health food stores.

Myth #2: Omega-3 supplements contain too much mercury

Fish living in their natural environment may be exposed to high levels of mercury, PCBs (polychlorinated biphenyls), dioxins and other environmental contaminants. However, it’s important to take a step back and see how the benefits of eating fish regularly or taking an omega-3 supplement outweigh the potential risks.

Some fish have lower levels of contaminants than other fish. For example, wild salmon has a lower level of contaminants compared to swordfish and tilefish. To learn more on seafood recommendations and to compare the contaminant levels of fish check out the Monterey Bay Aquarium Seafood Watch.

In terms of omega-3 supplements, manufacturers purify the oil in order to reduce the level of environmental contaminants. GOED also sets quality standards for its member companies to follow, and GOED randomly tests to ensure these standards are being met. Soon you may see a “Proud GOED Member” logo on supplement bottles (more information can be found here:

If you choose to take an omega-3 supplement, most health professionals recommend 250mg to 500mg of combined EPA and DHA per day for adults.

Myth #3:  You should stop taking omega-3s before surgery since it can cause excessive bleeding

This myth supposedly originated from the Greenlandic Inuit, a group of people who lived on whale blubber, which has a good amount of omega-3s. Scientists found that the Inuit, who consume high amounts of omega-3s  in their diet, also had significantly longer bleeding times compared to Danish people, creating the association between omega-3 intake and longer bleeding times. For some reason, this myth perpetuated for years.

However, a systematic review published in 2017 in the Danish Medical Journal found no evidence to support this statement. Data collected from 16 studies on people undergoing surgery found that fish oil did not increase bleeding time. In addition, the American Heart Association’s Science Advisory published in 2017 in the journal Circulation found that there was “little evidence of major adverse effects such as stroke or bleeding associated with omega-3 supplementation.”

In 2018 a study also published in Circulation examined the relationship between fish oil supplementation and bleeding that occurred from the time the patient goes into the hospital, clinic, or doctor’s office for surgery until the time of discharge. In this multinational, placebo-controlled study 1,516 subjects were either randomly assigned to receive EPA and DHA omega-3s before, during and after surgery or a placebo.  The results found that not only does taking EPA and DHA omega-3s not lead to increased bleeding, but also that there was a direct positive effect: people with the highest levels of EPA and DHA in their blood before surgery had the lowest risk for bleeding and less need for blood transfusions during surgery

These studies all concluded that there is no scientific basis to discontinue taking omega-3 supplements before surgery.

Myth #4: When it comes to protecting the heart, omega-3s supplements aren’t effective

A recent study looked at whether taking 2,000 IU daily of vitamin D3 and/or 1g of omega-3s (supplying 840 mg of EPA and DHA) reduces the risk of major cardiovascular events, that is: heart attack, stroke, or death related to cardiovascular disease (CVD). This study is called The VITamin D and OmegA-3 Trial (VITAL), and was conducted among 25,871 older adults (50 years and older), over the course of five years. At the end of the study, when all these cardiovascular events were looked at as a whole, researchers determined that there was no meaningful reduction to major cardiovascular events. However, when you take a closer look at the data there were numerous significant findings that did show a reduction with regards to specific cardiovascular events (you can get a detailed look at the results here).

Although there was much hype in the media – including vastly different headlines depicting the same study and its results! – it is important to look at the big picture of omega-3 research to see how VITAL fits into the more than 4,000 human clinical trials on EPA and DHA omega-3s. A closer look at VITAL actually strengthens the evidence that omega-3s help reduce the risk for coronary heart disease (CHD) and non-fatal heart attacks.   

Bottom Line:

When it comes to nutrition and omega-3s, the information can get confusing! If you have questions, you can always head to the GOED website, or their Instagram, Facebook and Twitter pages.


1 Comment
  • Yas
    Posted at 17:38h, 26 June Reply

    Thanks for including details on plant-based vs fish Omega-3, very helpful

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