Vitamin B12 and folic acid supplementation does not improve cognitive performance in elderly patients with elevated levels of an amino acid linked to Alzheimer's disease and memory loss.
Contrary to findings from early observational studies, vitamin B12 and folic acid supplementation does not improve cognitive performance in elderly patients with elevated levels of an amino acid linked to Alzheimer’s disease and memory loss, according to randomized placebo-controlled trial results published online in Neurology on November 12, 2014.
In one of the largest trials to date on the impact that long-term supplement use has on memory, researchers investigated the effects of 400 µg folic acid and 500 µg vitamin B12 supplementation taken daily over a 2-year period on the cognitive performance of patients aged 74 years, on average, with homocysteine levels between 12 and 50 µmol/L.
At the conclusion of their study, the authors found homocysteine concentrations decreased 5 µmol/L in the vitamin group and 1.3 µmol/L in the placebo group. Nevertheless, performance on tests of episodic memory, attention and working memory, information processing speed, and executive function did not differ over time between the 2 groups.
As a result, the investigators concluded that their research “provides Class I evidence that 2-year supplementation with folic acid and vitamin B12 in hyperhomocysteinemic elderly people does not affect cognitive performance.”
“Since homocysteine levels can be lowered with folic acid and vitamin B12 supplements, the hope has been that taking these vitamins could also reduce the risk of memory loss and Alzheimer’s disease,” said study author Rosalie Dhonukshe-Rutten, PhD, of Wageningen University in the Netherlands, in a press release from the American Academy of Neurology. “While the homocysteine levels decreased by more in the group taking the B vitamins than in the group taking the placebo, unfortunately there was no difference between the 2 groups in the scores on the thinking and memory tests.”