Primary Care in Rochester and Kasson

Answers to 5 questions about fish oil supplements

4/15/2021 by Allison Ducharme-Smith, M.D.

Fish Oil Supplements

The media is full of ads and recommendations for you to buy and take fish oil supplements to cure a list of health worries. But, are fish oil supplements really what you need? 

What is fish oil?

Fish oil is the fat, or oil, that comes from fish tissue. The reason you hear so much about it is because it is loaded with beneficial omega-3 fatty acids, specifically docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Your body cannot make these omega-3 fatty acids, so you must get them from food or supplements. 

Omega-3 fatty acids are important for your muscles, specifically your heart muscle. They can reduce the risk of heart attacks; high cholesterol, particularly triglycerides; and high blood pressure. But more than that, omega-3 fatty acids play a role in brain function and inflammation. Being deficient in omega-3 fatty acids has shown to be associated with issues including cardiovascular disease, rheumatoid arthritis, depression and Alzheimer's disease. 

Should you go and buy a bunch of fish oil supplements?

While it's known that omega-3 fatty acids are good for you and being deficient is bad, taking high doses of fish oil supplements does not necessarily correlate to better health. In large studies examining the effects of fish oil supplements on health, the evidence was mixed. 

These supplements did not appear to reduce the risk of heart attacks, strokes, or heart-related deaths in men and women. Moreover, there were some side effects, including bad breath and heartburn, and at high doses, an increased risk of bleeding. However, looking deeper, several specific groups benefited from fish oil supplements, and the exact dose of the supplement seemed to matter, as well. 

Who benefits from taking fish oil supplements?

As studies have shown, it is not a one-size-fits-all scenario. These studies showed that these specific groups may benefit from daily fish oil supplements:

  • Patients who eat less than 1.5 servings of fish a week or don't eat any fish. 
  • African American patients. 
  • Patients with high triglyceride levels, that is those patients whose triglyceride level is greater than 200 milligrams per deciliter. 

If you are a member of one of the groups that benefits from fish oil supplements, how much should you take and when should you take it?

The American Heart Association recommends that those who might benefit from fish oil supplements should take 1 gram per day of EPA plus DHA. Preferably this should come from consuming oily fish, but supplements can be considered. For patients with high triglycerides in particular, the American Heart Association concludes that a prescription fish oil supplement of 4 grams per day of EPA, or EPA + DHA, can be used to lower triglyceride levels. 

It is recommended to take the supplement prior to your largest meal of the day if you can, as doing so will help mitigate the rise in triglycerides that occurs with the largest meal. As always, consult with your health care provider before starting a fish oil supplement. 

What else can you do to lower your risk of heart disease?

The best thing you can do to lower your risk of heart disease is lead a healthy lifestyle and consume a healthy diet. This means not smoking, eating at least five servings of fruits and vegetables daily, and getting moderate exercise for at least 150 minutes a week. 

If you are a healthy person and at low or average risk for heart disease, you should eat at least two servings a week of fatty fish, such as salmon, tuna or herring. It is better to eat your omega-3 fatty acids in food rather than a supplement. 

Allison Ducharme-Smith, M.D., is an internal medicine physician in Primary Care in Rochester and Kasson's Division of Community Internal Medicine, she practices at Mayo Family Clinic Northeast in Rochester. Her interests include preventive medicine, women's health, chronic disease management and medical education.