Use B-Complex Vitamins and DHA to Keep Your Brain Sharp as You Age

If you want to keep your marbles as you grow older, it may be worthwhile focusing on two nutrients: B-complex vitamins and docosahexaenoic acid (DHA), one of the omega-3 fats found in fish oils. Three recent studies have found that these nutrients play major roles in keeping the brain sharp.

In the first study, A. David Smith, PhD, of Oxford University, England, and his colleagues analyzed data from 168 men and women they treated with either B-vitamins or placebos. The subjects’ brain changes were also tracked with MRIs (magnetic resonance images) of the brain.

The supplements consisted of 800 mcg of folic acid, 500 mcg of vitamin B12, and 20 mg of vitamin B6 daily, which the subjects took for two full years. The study participants had been diagnosed with mild cognitive impairment and brain atrophy – problems likely to develop into Alzheimer’s disease. Smith also measured the subjects’ blood levels of homocysteine, one of the markers of B-vitamin deficiency and a risk factor for cardiovascular disease and Alzheimer’s. People taking the B vitamins experienced an average of 30 percent less brain shrinkage, but some of the patients had more than a 50 percent reduction in brain shrinkage, compared with those in the placebo group. Homocysteine levels also decreased significantly among those taking B vitamins, and the rate of response was related to initial homocysteine levels. People with higher homocysteine levels were more likely to benefit from the B vitamins.

In the second study, Giuseppe Astarita, DSc, of the University of California, Irvine, and his colleagues compared brain and liver levels of DHA in 37 people with Alzheimer’s and 14 without the disease. All of the tissues samples were obtained post mortem. People with Alzheimer’s had lower levels of DHA, which is a precursor for neuroprotective compounds. “There were statistically detectable differences in DHA content in all [brain] regions examined,” Astarita wrote.

Astarita determined that the low levels of DHA were related to a defect in the liver’s ability to convert tetracosahexaenoic acid (THA) to DHA. THA is the immediate metabolic precursor to DHA, and the conversation requires “D-bifunctional protein.” People with Alzheimer’s appear to lack the ability to make this particular protein. The finding “led us to hypothesize that the alteration in brain DHA might result from a systemic deficiency in the biosynthesis of this fatty acid,” Astarita wrote. Although Astarita did not explicitly suggest it, his research left open the possibility of using DHA supplements to bypass this defect.

Finally, Matthew F. Muldoon, MD, of the University of Pittsburgh in Pennsylvania and his colleagues measured blood levels of three omega-3 fats – alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and DHA – in 280 people between the ages of 35 and 54 years. None of the subjects had been taking omega-3 supplements.

People with higher levels of DHA performed better on tests given to gauge reasoning, mental flexibility, memory, and vocabulary. Muldoon wrote that the omega-3s are “emerging as important nutrients for optimal brain development and for possible protection against brain senescense…it is plausible that insufficient dietary intake is related to relatively poor cognitive abilities or performance throughout the lifespan…”

SOURCE: Nutrition Reporter,  Jack Challem. Nov. 2010 Vol.21 No.11

References: Smith DA, Smith SM, de Jager CA, et al. Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment: a randomized controlled trial. PLoS One, 2010;5:e12244. Astarita G, Jung KM, Berchtold NC, et al. Deficient liver biosynthesis of docosahexaenoic acid correlates with cognitive impairment in Alzheimer’s disease. PLoS One, 2010;5:e12538. Muldoon MF, Ryan CM, Sheu L, et al. Serum phospholipid docosahexaenoic acid is associated with cognitive functioning during middle adulthood. Journal of Nutrition, 2010;140:848-853. !