- CONDITION CENTERS
A meta-analysis of 8 randomized controlled trials reports that, overall, folic acid supplementation reduced the risk for a first stroke by 18%. The stroke risk reduction was about 25% in subgroups that received supplements for more than 3 years, had blood homocysteine levels that decreased by 20% or more, or lived in regions with no folate grain fortification. There was no significant risk reduction in the corresponding subgroups without these characteristics. Although these data appear promising, experts caution that further randomized studies are needed before folic acid can be recommended for primary prevention of stroke.