What does eicosapentaenoic acid do?

Attention-Deficit Hyperactivity Disorder (ADHD)

Because children need omega-3 fatty acids for their brains to develop properly, researchers have looked at whether fish oil might reduce ADHD symptoms. So far, results have been mixed. One study showed fish oil might help, but many people dropped out of the study before it was done.

Depression

Some studies show that fish oil reduces symptoms of depression. Other studies suggest it may be a kind of EPA known as ethyl-EPA (and not DHA) that reduces symptoms.

Heart Disease

Fish oil seems to help people who already have heart disease. It also may lower the risk for developing heart disease. Omega-3 fatty acids found in fish oil help lower triglycerides and blood pressure, reduce the risk of blood clots, improve the health of arteries and reduce the amount of arterial plaque, which narrows arteries, and causes heart disease.

The American Heart Association (AHA) recommends eating fish, particularly fatty fish, at least 2 times a week. Fatty fish include salmon, herring, lake trout, sardines, and albacore tuna. People with existing heart disease may need fish oil supplements in addition to adding more fish to their diet. Ask your doctor if fish oil supplements would be right for you.

Rheumatoid Arthritis

Several small studies indicate that fish oil may help reduce symptoms and inflammation from rheumatoid arthritis. However, it does not stop joint damage from getting worse.

Menopause

One study found that EPA reduced the number of hot flashes by 1.58 per day in menopausal women. It did not decrease the severity of the hot flashes, however.

Menstrual Pain

Fish oil appears to reduce the pain of menstrual cramps when taken on a regular basis (not just when menstruating).

Raynaud Syndrome

Several studies show that high doses (12 g) of fish oil can make fingers and toes less sensitive to cold when people have Raynaud syndrome. Doses this high should be taken only under a doctor's supervision.

Lupus

Two small studies suggested that fish oil reduced fatigue and joint pain from lupus.

Other Conditions

Omega-3 fatty acids, including EPA, may also have positive effects on lung and kidney diseases, type 2 diabetes, obesity, ulcerative colitis, Crohn disease, anorexia nervosa, burns, osteoarthritis, osteoporosis, and early stages of colorectal cancer.