Fish haters can get strong bones too

NEW YORK (Reuters Health) - Diets high in alpha-linolenic acid may promote strong bones, the results of a small study suggest, and contrary to what many people believe, you don't need to eat fish or take fish oil tablets to raise levels of this omega-3 fatty acid.

Omega-3 fatty acids are a type of polyunsaturated fatty acid, or PUFA. Most guidelines recommend consuming diets high in PUFAs and low in saturated fats.

"Our findings suggest that by eating plant sources of alpha-linolenic acid, such as walnuts and flaxseed oil, you can strengthen bones," senior author Dr. Rebecca L. Corwin, from The Pennsylvania State University, University Park, told Reuters Health. "This is good news for people who don't like fish."

The new findings, which appear in the Nutrition Journal, are based on a study of 23 subjects who consumed one of three diets, provided by the researchers, over 6-week periods. The diets included an average American diet, which was low in PUFAs; a diet high in alpha-linolenic acid; and a diet high in linoleic acid, a PUFA of the omega-6 group.

Compared with the average American diet, the alpha-linolenic diet, and to a lesser extent the linoleic diet, produced changes suggesting a reduction in bone breakdown, which would be expected to promote stronger bones. However, these diets did not seem to increase the formation of new bone.

"The take-home message is that eating plant sources of omega-3 fatty acids" seems to improve bone health, Corwin noted. "Although linoleic acid also had a beneficial effect, I would be reluctant to recommend increasing the intake, since some research has linked the omega-6 fatty acids with inflammatory effects."

SOURCE: Nutrition Journal, January 16, 2007.