Eat fatty fish like salmon at least two times a week.

Do You Need Fish Oil Supplements If You Eat Fish?

by Michelle Kerns

Fish oil supplements are one of the fastest growing segments of the supplement industry, with Americans spending over $1 billion dollars on fish oil annually. The supplements have been touted as a treatment or preventative measure for everything from menstrual pain and obesity to depression and Alzheimer's disease; fish oil supplements marketed for children claim to improve brain function and decrease attention deficit hyperactivity disorder symptoms. However, MedlinePlus cautions there are only a few conditions that scientific research has confirmed can be safely and effectively treated with fish oil supplements. If you don't have these conditions, you may be better off skipping the supplements in favor of fresh fish.

Fish Oil Recommendation

The American Heart Association recommends that the only people who should take fish oil supplements in addition to regularly eating fish are individuals with a history of heart disease or with high blood triglyceride levels. If you don't fall into one of these categories, the AHA says that you'll get adequate amounts of the beneficial omega-3 fatty acids contained in fish oil by eating a 3.5-ounce serving of fatty fish at least two times a week. For children, 1 ounce of cooked fish is equivalent to one serving.

Special Considerations

Young children, pregnant and nursing women and women who are trying to become pregnant are better off eating fresh fish instead of taking fish oil supplements, but they need to be careful about the type and amount of fish they eat, says the U.S. Food and Drug Administration. Fish such as king mackerel, tilefish, shark and swordfish may contain high concentrations of mercury, which can harm the growth and development of an infant's or child's nervous system. Avoid these fish and try to limit yourself and your young children to 12 ounces a week of a variety of seafood such as salmon, catfish or canned light tuna.

Best Fish to Choose

To help you choose seafood that's not only low in contaminants like mercury and polychlorinated biphenyls, or PCBs, and high in omega-3 fatty acids, but also caught in a sustainable and environmentally friendly way, the Monterey Bay Aquarium's Seafood Watch has compiled The Super Green List of fish and shellfish. According to the list, your best choices include wild-caught Alaskan salmon, freshwater coho salmon, troll- or pole-caught albacore tuna, farmed oysters, wild-caught Pacific sardines and farmed rainbow trout. Other good choices that contain a slightly lower concentration of omega-3 fatty acids include farmed mussels, Arctic char and wild-caught Dungeness crab.


If you do choose to take fish oil supplements, ask your doctor to help you determine a safe dosage and don't take more than that amount. Taking more than 3 grams of fish oil a day may significantly increase your risk of bleeding excessively if you're hurt or injured. It may also suppress your immune system and make you more likely to develop recurrent infections. Fish oil supplements can cause side effects like skin rashes, an upset stomach, diarrhea, heartburn and bad breath. Avoid using supplemental fish oil if you have diabetes, liver disease or a neurological disorder like bipolar disorder or depression. Tell your doctor if you're on birth control pills, orlistat or hypertension drugs such as enalapril since fish oil may interfere with the function of these medications.

About the Author

Michelle Kerns writes for a variety of print and online publications and specializes in literature and science topics. She has served as a book columnist since 2008 and is a member of the National Book Critics Circle. Kerns studied English literature and neurology at UC Davis.

Photo Credits

  • Creatas/Creatas/Getty Images