A large-scale, long-term study of vitamin B⁶ showed that it may be effective in reducing the risk of Parkinson's disease (PD). Researchers in Amsterdam followed 5289 men and women aged 55 and older for nearly 10 years in an effort to determine whether a higher intake of folate and vitamins B⁶ and B¹² would reduce the risk of PD, as all 3 are known to reduce homocysteine levels. At the beginning of the study, none of the patients had PD. In the 10 years of followup study, however, 72 people developed the disease. While no link could be made between levels of B¹² or folate and PD risk, researchers were able to determine that the more B⁶ people consumed, the lower their PD risk. People in the top third of B⁶ intake were 54% less likely to develop PD than those people in the lowest third. According to researchers, this result is significant only among smokers, suggesting that the vitamin does not lower PD risk by any effect on homocysteine levels but rather by protecting brain cells from free radicals. They point to other studies that suggest smoking reduces PD risk because of nicotine's ability to protect brain cells. Researchers do not want to suggest that B¹² and folate are not protective, but rather further studies are needed to examine the blood's nutrient levels. The study can be found in the July 2006 issue of Neurology.

Ms. Farley is a freelance medical writer based in Wakefield, RI.