UPDATE: Omega-3 Fatty Acids

First the good news: Omega-3 fatty acids reduce post-partum depression by as much as 50 percent. This seems to indicate that the post-partum depression is, at least in part, a nutritional deficiency. While pregnant and nursing, the infant gets priority use of any omega-3 fats in the mother's diet. Since most Americans are deficient in this essential fat anyway, consuming more will help the baby to grow a large, well-functioning brain and keep the mother from becoming deficient and depressed.

Now the bad news: omega-3 fats do not seem to offer any protection against cancer, at least not in the latest meta-study.

Researchers examined data from 38 studies that tracked patients for up to 30 years, and said most showed there is no cancer protection from omega-3 fatty acids. Although a few studies found some risk reduction for cancers of the breast, prostate and lung, those studies were relatively small and not definitive, said Dr. Catherine MacLean, the lead author and a researcher at the Rand Corp. and Greater Los Angeles Veterans Affairs Healthcare System.

"It doesn't mean that omega-3 fatty acids don't have other health benefits — it's just that reducing cancer risk isn't one of them," MacLean said.

However, the review is unlikely to be the last word on the issue. Diet is known to play a role in cancer and the researchers evaluated observational studies, which provide mostly circumstantial evidence.

The reviewed studies examined the effects of fish oil — in both pill form and as food — on 11 kinds of cancer, mostly tumors of the breast, colon, lung or prostate.

Emphasis added. You still need to be getting omega-3 fats in your diet for a myriad of health reasons.