Does B12, Folic Acid Improve Cognition in Hyperhomocysteinemic Patients?

the MPR take:

The results of a two year study on the effects of vitamin B12 and folic acid supplementation in improving cognitive performance in elderly patients with increased homocysteine levels have been published in the journal Neurology. Previous studies have shown a link between elevated plasma homocysteine levels and cognitive decline and dementia, so researchers sought to find out whether supplementing with folic acid and vitamin B12, both known to lower homocysteine levels, could also benefit cognitive performance. The study included 2,919 healthy, elderly patients with homocysteine levels between 12–50μmol/L; participants received either a tablet containing vitamin B12 500mcg + folic acid 400mcg or placebo (both tablets contained vitamin D3 15mcg). After two years of supplementation, the study did not reveal beneficial effects on four cognitive domains: attention and working memory, episodic memory, executive function, and information processing speed. However, the rate of decline in global cognition was slightly lower in the B-vitamin group, though this effect could be attributed to chance. The authors conclude that in healthy, elderly, hyperhomocysteinemic patients, two year supplementation with folic acid and vitamin B12 does not appear to affect cognitive performance.  It is possible the authors say, that the beneficial effects of supplementation may not have revealed themselves at the time of measurement.

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Does B12, Folic Acid Improve Cognition in Hyperhomocysteinemic Patients?

Objective: We investigated the effects of 2-year folic acid and vitamin B12 supplementation on cognitive performance in elderly people with elevated homocysteine (Hcy) levels. Methods: This multicenter, double-blind, randomized, placebo-controlled trial included 2,919 elderly participants (≥65 years) with Hcy levels between 12–50mol/L.