Fish oil: friend or foe?



The answer is friend rather than foe, especially when the fish oil comes from food sources rather than supplements.

Omega-3 fatty acids in balance

What is special about fish oil? It’s loaded with omega-3 fatty acids. These must come from food, as our body cannot produce them.

The two most important omega-3 fatty acids are docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Oily fish like salmon, mackerel, and sardines are rich in these omega-3 fatty acids. Some plants are rich in another type of omega-3 fatty acid, alpha-linolenic acid, which the body can convert into DHA and EPA. Good sources for this are flax seeds, chia seeds, walnuts, pumpkin seeds, and canola oil.

Omega-3 fatty acids play an important role in brain function, normal growth and development, and inflammation. Deficiencies have been linked to a wide variety of health problems, including cardiovascular disease, some cancers, mood disorders, arthritis, and more. However, that doesn’t mean that taking high doses will lead to better health and disease prevention.

Fish oil supplements have been touted as an easy way to protect the heart, reduce inflammation, improve mental health, and extend life. Such claims are one reason Americans spend more than $ 1 billion annually on over-the-counter fish oil. And food companies add it to milk, yogurt, cereal, chocolate, cookies, juices, and hundreds of other foods.

But the evidence for improving heart health is mixed. In November 2018, a study published in the New England Journal of Medicine found that omega-3 fatty acid supplements failed to reduce heart attacks, strokes, or deaths from heart disease in middle-aged men and women with no known risk factors for heart disease. Previous research published in the same journal in 2013 also showed no benefit in people with risk factors for heart disease.

However, when researchers looked at subsets of people who didn’t eat fish, the results suggested that they could reduce their cardiovascular risk by taking a fish oil supplement.

Evidence linking fish oil and cancer can be found all over the map. Most research, including the 2018 study cited above, has not shown a reduced risk of cancer. However, some previous research suggested that a diet high in oily fish or fish oil supplements might reduce the risk of certain types of cancer.

Take the message home with you

How food and its components affect the body is largely a mystery. This makes the use of dietary supplements for anything but treating a deficiency questionable.

Despite this one study, you should still consider eating fish and other seafood as a healthy strategy. If we could absolutely, positively say that the benefits of eating seafood come entirely from omega-3 fats, then taking fish oil pills would be an alternative to eating fish. But more than likely you will need the full orchestra of fish fats, vitamins, minerals, and supportive molecules, rather than the solitary notes of EPA and DHA.

The same goes for other foods. Ingesting just a handful of supplements is no substitute for the abundance of nutrients you get from eating fruits, vegetables, and whole grains.

What Should You Do If You Are Currently Using Fish Oil? If your doctor has prescribed them – they are a legal and effective treatment for people with high levels of triglycerides in the blood – follow their instructions until you can have a conversation about fish oil.

If you are taking them on your own because you believe they are good for you, it is time to reconsider that strategy. If you’re not eating fish or other seafood, you can benefit from a fish oil supplement. You can also get omega-3 fatty acids from ground flaxseed or flaxseed oil, chia seeds, walnuts, rapeseed oil, and soybean oil. One to two servings a day can help you avoid an omega-3 fatty acid deficiency.

Following the simple advice of food writer Michael Pollan when choosing a diet might be the best way to go: “Eat food. Not too much. Mostly plants.”

Image: Batteries not included / Getty Images

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