Cognitive decline is a loss of memory, intellectual, and social skills. It can lead to a loss of independent function and disability. The decline can be caused by a number of reasons. Some researchers have suggested that high levels of homocysteine in the blood may contribute to the loss. But B vitamins, found in foods or supplements, are believed to reduce homocysteine levels in the blood.
The Women’s Antioxidant and Folic Acid Cardiovascular Study is a large trial designed to study the benefits of B vitamins and folic acid against heart disease. Researchers from Channing Laboratory used information from this study as a basis to also study cognitive decline in women. The study, published in the American Journal of Clinical Nutrition, found that B vitamin supplementation did not delay cognitive impairment.
The Women’s Antioxidant and Folic Acid Cardiovascular Study is a randomized controlled trial. It has followed a select group of women since 1998. Some of the participants were randomly assigned to receive B vitamins, while others received a placebo. Researchers began to measure cognitive function in 2,009 of the participants. Cognitive function was measured through a telephone test given four times over a five-year period. The test evaluated:
The results did not show a significant difference in cognitive decline between the women taking supplements and the women taking a placebo.
Some evidence, however, suggested that women who had low dietary vitamin B may have had some protection against cognitive decline with the supplement.
Further study will need to be done to determine the exact benefit of supplementation in a low vitamin B diet. Vitamin supplements can be expensive. Ask your doctor if you should take them.
Maintaining a healthy cardiovascular system, including healthy blood vessels, can help prevent or delay some cognitive decline. Maintaining a healthy system includes a diet rich in fruits and vegetables. This will give you an ample supply of vitamins and antioxidants. Regular physical activity has also been shown to slow the rate of cognitive decline.
American Dietetic Association
Kang JH, Cook N, Manson J, Burimng JE, Albert CM, Grodstein F. A trial of B vitamins and cognitive function among women at high risk of cardiovascular disease.AM J Clin Nutrition.2008 Dec;88(6):1602-1610.
Last reviewed March 2009 by Larissa J. Lucas, MD