The numerous claims for fish oil may start to sound a bit, well, fishy. But on closer inspection, this supplement really does have some promising effects derived from the healthy fat it delivers.
How It Works
Fish oil contains two omega-3 fatty acids called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are found almost exclusively in seafood. At doses of about 250 milligrams per day, EPA and DHA reduce the risk of coronary heart disease and sudden cardiac death, says Dariush Mozaffarian, M.D., Dr.P.H., a cardiologist and assistant professor at Harvard Medical School who studies omega-3s. “This equates to one to two oily fish meals per week,” he says. “As you increase omega-3 intake from there, you may see more benefits in other risk factors for heart disease, such as a reduction in high blood pressure, triglycerides, and inflammation.” Also, DHA is the main polyunsaturated fatty acid found in the brain and plays an important role in brain development and function.
Research shows that omega-3 benefits include lower triglyceride levels and a reduced growth rate of plaque. In a 1999 study published in Lancet, Italian researchers gave capsules containing 870 mg of EPA/DHA to more than 11,000 heart attack survivors. Death from any cause decreased by 20 percent and sudden death dropped by 45 percent compared with patients not taking the pills. And there are even more possible health boosts. A 1995 review of research in the Journal of Clinical Epidemiology reported that rheumatoid arthritis patients supplementing with fish oil enjoyed a significant decrease in tender joints and morning stiffness. In a 2006 study, Harvard researchers found that increased consumption of fish (especially two or more weekly servings) reduced the risk of age-related macular degeneration. And University of Pittsburgh researchers reported this year that people low in omega-3s were more likely to have a negative outlook, while those with higher omega-3 blood levels were more agreeable and less likely to be depressed.
How to Take It
The American Heart Association doesn’t endorse a supplement for those without heart disease—they instead recommend eating a variety of fatty fish (salmon, herring, trout, sardines, anchovies) at least twice a week. (Fish also offers the bonus of protein and selenium.) For those with heart disease, the AHA advises eating about 1 g of EPA/DHA per day, preferably from fish, and that a fish oil supplement could be considered in consultation with your healthcare provider. But if you don’t like seafood, Mozaffarian says, you should at least think about taking a low-dose supplement. “Even if you don’t have heart disease, there’s no other nutrient like omega-3s for cardiovascular health,” he says. Supplement doses range from about 300 mg to 500 mg per day from a combination of EPA and DHA.
Enteric-coated capsules can help prevent “fish burps” by delaying digestive breakdown, and some products offer a lemon flavor to counteract the fishy aftertaste. For women of childbearing age and for young children, the government recommends including up to two servings per week of fish or shellfish because of their many nutritional benefits, being careful to avoid four species— tilefish, king mackerel, shark, and swordfish—because of their high mercury content (www.cfsan.fda .gov/~dms/admehg3.html for more details). One recent study indicates that when a pregnant woman eats less than 12 ounces of fish a week, she significantly increases the risk of her children having low verbal IQ and developmental problems.