Pregnant women have been counseled to take fish oil to reduce the risk of postpartum depression, but a new study says this strategy doesn’t work. The Australian researchers gave 2,000 pregnant women either vegetable oil as a placebo or fish oil capsules with 800 mg DHA daily and 100 mg EPA. Fortunately, the study uncovered only one uncomfortable effect: the typical fish oil burp was twice as common among women taking fish oil as among those taking vegetable oil. But the main results were disappointing.
The women taking fish oil were no less likely to experience postpartum depression, and their infants were no more advanced in language or cognitive behavior at a year and half than those on placebo. They were, however, less likely to give birth prematurely. That risk dropped from two percent to about one percent. Pregnant women are often warned not to eat king mackerel, tilefish, shark or swordfish because these fish are high in mercury. Although fish oil does not have mercury, it does not seem to offer great benefits.
[Journal of the American Medical Association, Oct. 20, 2010]