Omega-3 fatty acids are important for brain health. They help build brain cells and maintain brain function throughout your life. Two important fatty acids—eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)—are considered essential nutrients because your body can’t make them on their own. They are found mostly in fish (such as salmon, trout, herring, tuna, and mackerel). But if you don’t like fish, some other foods—such as eggs, walnuts, flaxseeds, and brussels sprouts—contain alpha-linolenic acid (ALA), a third type of fatty acid that converts to EPA and DHA in the body in limited amounts. You can also get omega-3 fatty acids through dietary supplements (such as fish oil) marketed for heart and brain health. Today, fish oil supplements are one of the most popular dietary supplements on the market.

Omega-3 fatty acids from food can help overall brain health, but it’s unclear whether omega-3 dietary supplements can help boost brain health and optimize cognitive performance.

The American Heart Association and the American Psychiatric Association recommend at least 2 servings of fish per week (an average daily intake of 450–500 mg EPA and DHA combined) for overall heart and mental health. However, most people don’t consume enough of the foods they need to get the recommended amount of omega-3.

In 1997, FDA announced that up to 3 grams per day of EPA + DHA from fish-oil dietary supplements is “generally recognized as safe.” FDA has concluded that up to 5 grams per day of omega-3 from dietary supplements is safe.

Can omega-3 dietary supplements boost brain health?

Some of the latest research on omega-3 dietary supplements has looked at their effects on brain health and enhanced cognitive performance. Some of this research shows enhanced performance on tasks related to attention and memory after taking 2 to 2.5 grams per day of fish-oil dietary supplements (at various ratios of EPA and DHA) over the course of 3 to 6 months. Other research shows no benefit at all. Some of this research lacks crucial information, which makes it difficult to conclude that omega-3 dietary supplements will help you enhance your performance.

Can omega-3 dietary supplements negatively affect performance?

Minor side effects include possible burping, fishy aftertaste, upset stomach, headache, or flu-like symptoms.  According to some reports, extremely high amounts (more than 20 grams per day), taken over a long time, might reduce immune function, but also might lead to increased risk of bleeding and potential stroke when used in combination with certain medications.

The bottom line about omega-3

The information presented above is only for people with no signs of cognitive decline. For a look into the latest research on omega-3 dietary supplements and brain injury, please read the OPSS article on that topic. As a Military Service Member, look first to foods for the omega-3 fatty acids you need.


Updated 19 July 2021


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