Several years ago studies suggested that high levels of homocysteine, a naturally occurring amino acid in the blood, could be harmful to cardiac health. B vitamin supplementation is known to lower blood levels of homocysteine. According to the thinking at that time lowering homocysteine levels by taking B vitamins such as B6 and Folic acid should then improve cardiac health. A great deal of publicity surrounding the supposed cardiac benefits of these vitamins led to the promotion of prescription strength B vitamin preparations such as Folbee. These expensive vitamin preparations were then routinely prescribed by physicians for cardiac protective purposes.

Since then several large studies showed no cardiac benefit of lowering homocysteine levels. Worse still, a study just published April 28, 2010 in the Journal of the American Medical Association shows that B vitamin supplementation in diabetics with kidney problems can lead to a doubling of risk of heart attack, stroke or dying. Diabetics with kidney disease are already at higher risk for developing these problems but adding the B vitamins makes the situation much worse. Additionally, kidney function declined faster in those on B vitamin supplements.

The lesson here is to be careful before adopting new therapies based on unsubstantiated research, particularly if you are more vulnerable due to pre-existing medical conditions.

Gary Pepper, M.D., Editor-in-Chief, metabolism.com