DHA Reduces Dementia, AD Risk

BOSTONHigher levels of plasma phosphatidylcholine (PC) docosahexaenoic acid (DHA) may significantly cut the risk of developing dementia and Alzheimers disease (AD), according to data from the Framingham Heart Study. Published in the Archives of Neurology (63:1545-50, 2006), the study was headed by researchers from Tufts Universitys Lipid Metabolism Laboratory at the Jean Mayer U.S. Department of Agriculture (USDA) Human Nutrition Center on Aging. The prospective nine-year follow-up study compared plasma PC fatty acid levels at baseline and studys end in 899 men and women (median age 76) free of dementia at baseline. During follow-up, 99 new cases of dementia (including 71 of Alzheimers disease) occurred. Compared with subjects in the lower three quartiles of baseline plasma PC DHA levels, subjects in the upper quartile had a 47-percent reduced risk of developing all-cause dementia and a 39-percent reduced risk of developing AD; DHA was the only specific fatty acid that showed a significant correlation. Subjects in the upper quartile had a mean DHA intake of 0.18 g/d and a mean fish intake of three servings per week in a subset of 488 participants.

In a related editorial in the same issue (63:1527-28, 2006), Martha Claire Morris, ScD, associate professor at the Rush University Medical Center, Chicago, called the findings important in a young field studying the link between diet and neurodegenerative diseases.