Age-related cognitive decline is becoming increasingly common, with Mild Cognitive Impairment affecting over 4 million older persons in the US. Some studies have suggested that certain dietary patterns – particularly those rich in omega-3s and B vitamins – might be important in slowing this trend. University of Oxford researchers investigated whether the effect of B vitamin supplementation on the rate of brain shrinkage (atrophy) depends on omega-3s. Their results are described in detail in the July 2015 issue of The American Journal of Clinical Nutrition.
This research was an offshoot of the Homocysteine and B Vitamins in Cognitive Impairment (VITACOG) study, a 2-year randomized clinical trial originally designed to evaluate the effect of taking B-vitamin supplements on the rate of brain atrophy. A total of 168 elderly subjects (average age: 77 years) with Mild Cognitive Impairment participated; 85 took a B-vitamin supplement daily while the remaining subjects took a placebo pill. Blood plasma was analyzed for omega-3s, and brain atrophy was evaluated using magnetic resonance imaging (MRI) scans at the beginning and end of the study. The researchers found strong evidence that vitamin B supplementation markedly slows brain atrophy, but only in individuals with adequate omega-3 status. Their results can also be interpreted as suggesting that increased omega-3 intake can lower risk for brain atrophy, but only when B vitamin intake is also adequate.