Our brains shrink as we age–especially as we get to be over 70 years old. However, it appears that taking a vitamin B supplement that contains folic acid and B12 may be good for our brains as we age. This shrinkage appears to be more gradual in people with emerging signs of dementia and much faster in people with Alzheimer’s disease. According to a small British study, a daily dose of certain B vitamins may be able to reduce the rate of brain atrophy by up to 53%. By slowing the rate of brain shrinkage, the B vitamins folic acid and Vitamin B12 may allow us to enjoy clear memories and thoughts for a longer time.
High levels of homocysteine, a protein in the blood, have previously been associated with increased brain shrinkage and an increased risk of Alzheimer’s disease. Separately, the B vitamins folic acid, Vitamin B6, and Vitamin B12 are known to reduce blood homocysteine levels. This knowledge led the researchers to investigate whether supplementing these three B-vitamins might actually slow the rate of brain shrinkage in patients experiencing memory loss.
The researchers recruited people over 70 years old who had been diagnosed with early dementia and had been experiencing memory problems to participate in the study. They used data from 168 subjects in the final analysis.
Initially, all subjects underwent blood tests to measure homocysteine levels and cranial MRI to determine their brain volumes. Their scores on a telephone-based cognitive skills test were also recorded. The subjects were then divided into two equally-sized groups: a treatment group that received daily doses of folic acid, Vitamin B12, and Vitamin B6, and a control group that received a placebo pill. At the end of the two-year trial period, MRIs and blood tests were repeated for comparison to the initial measurements.
Overall, subjects who took the vitamins every day lowered their blood levels of homocysteine by 22% on average, compared to the placebo takers whose blood levels of homocysteine actually increased slightly over the course of the study. Furthermore, those who took the vitamins experienced a rate of brain atrophy 31% lower compared to patients in the control group. (Patients from the control group lost an average of 1.06% of brain volume per year, whereas patients who took the vitamin lost an average of 0.73% of brain volume per year.) Moreover, people with the highest initial homocysteine levels responded the best to the vitamin treatment. Vitamin-takers from this subgroup showed 53% less brain atrophy than control group-members with comparable homocysteine levels. Further blood analysis revealed that folic acid and vitamin B12 seemed to be more directly responsible for the beneficial effects than vitamin B6.
The researchers believe that certain B vitamins decrease homocysteine levels because they help an enzyme that breaks down homocysteine work properly. What they don’t know is whether homocysteine causes brain atrophy or is simply the by-product of another process that does. Furthermore, while the vitamin intervention did appear to slow the rate of brain shrinkage, the two-year study did not measure outcomes such as the development of dementia or Alzheimer’s disease, so it cannot be assumed that taking B-vitamin supplements is actually associated with a decreased risk of developing these diseases.
That’s worth the occasional trip to the pharmacy to stock up on a B-complex vitamin containing folic acid and Vitamin B12.