Numerous studies have outlined the benefits of omega-3 fatty acids but recommendations on how much you should get by people not trying to sell you something are less common.   A team of French scientists say they have found the dose of DHA - docosahexaenoic acid, found in cold water fatty fish and fish oil supplements - that is "just right" for preventing cardiovascular disease in healthy men.

In a research report appearing in the September 2009 issue of The FASEB Journal , the scientists say that a 200 mg dose of DHA per day is enough to affect biochemical markers that reliably predict cardiovascular problems, such as those related to aging, atherosclerosis, and diabetes. This study is the first to identify how much DHA is necessary to promote optimal heart health. 

To determine the optimal dose of DHA, Lagarde and colleagues examined the effects of increasing doses of DHA on 12 healthy male volunteers between ages of 53 and 65. These men consumed doses of DHA at 200, 400, 800, and 1600 mg per day for two weeks for each dose amount, with DHA being the only omega-3 fatty acid in their diet.

Blood and urine samples were collected before and after each dose and at eight weeks after DHA supplementation stopped. The researchers then examined these samples for biochemical markers indicating the effects of each dose on the volunteers.

"This study shows that regularly consuming small amounts of DHA is likely to improve the health status of people, especially in regards to cardiovascular function," said Michel Lagarde, co-author of the study. 

"Now that we have a very good idea about how much DHA is just right, the next step is to try it out in an expanded clinical trial that involves many more people," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "Until then, I'll stick with tasty foods that contain DHA, like fish, rather than getting a quick fatty-acid fix at the local vitamin store."