Vital Signs

To view this page ensure that Adobe Flash Player version 11.1.0 or greater is installed.

NU T R I T I ON Fish-Oil Supplements Offer Health Benefits for Some Conditions More than 50 percent of adults in the United States use dietary supplements, and fish oil is among the most popular. Although scientific evidence suggests that consuming fish-oil supplements to increase dietary intake of omega-3 fatty acids may safely and effectively provide specific health benefits for certain conditions, experts caution that fish-oil supplements are not a cure-all. “There is no question that fish oil has been effective in reducing high triglycerides, which are associated with heart disease and poorly controlled diabetes,” explains cardiologist Gregg C. Fonarow, MD, co-director of the UCLA Cholesterol, Hypertension and Atherosclerosis Management Program (CHAMP). According to Dr. Fonarow, the right dose to reduce triglycerides, or fats related to cholesterol in the blood, is about two-to-four grams daily. Fish-oil supplementation may also provide some benefit to patients with heart failure, Dr. Fonarow says. Recent studies suggest, however, it does not lower the risk for first or recurrent heart attacks among people with, or at high risk for, heart disease, particularly those who already take cholesterol-lowering statins. There is also conflicting evidence as to whether fish-oil supplementation is associated UCLAHEALTH.ORG 1-800-UCLA-MD1 (1-800-825-2631) with a lower risk for high blood pressure, diabetes, stroke or cardiac death. “Fish oil is not a panacea,” Dr. Fonarow emphasizes. “Although fish-oil supplements are generally safe and well-tolerated when used correctly, it does not make up for significant risk factors or unhealthy lifestyle behaviors, such as smoking.” Fish-oil supplementation may also benefit people with diagnosed depression, bipolar disorder and certain other mental illnesses, says UCLA psychiatrist Peter Dell, MD. But evidence about its effectiveness is mixed. “We have more robust evidence for the effectiveness of standard Western medicines in patients with depression or bipolar disorders,” Dr. Dell explains. “But for patients who don’t want to use standard Western medicine, I will usually consider prescribing fish-oil supplements because it can sometimes be effective with very few side effects.” He adds that the best evidence points to using fish oil in combination with standard Western medicines such as antidepressants rather than alone. He recommends that people should ask their doctors if fish-oil supplementation is appropriate for their condition. “If fish oil is cleared by their doctors, they should take 1,000 to 2,000 milligrams per day and make sure at least 60 percent of the omega-3 fatty acids in the supplements are EPA,” he says. Two of the most important omega-3 fatty acids contained in fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). “DHA does not appear to be helpful for mood, and may actually worsen problems,” Dr. Dell says. Fish oil also has demonstrated effectiveness outside of cardiovascular and mental health. In children with intestinal failure, for example, fish oil is safe and effective in helping to reverse liver disease and may also decrease the need for liver and/or intestinal transplants, as well as mortality, recent studies have shown. Although most experts say fish oil is likely safe for most people, including pregnant women and those who are breast- feeding, when taken in low doses, high doses should be taken only while under medical supervision. Many health experts recommend that people try to eat a healthy, balanced diet to protect against diseases and most cancers, and turn to supplements for extra help only when necessary.