Researchers examined data from eight large, randomized, placebo-controlled trials of folic acid supplementation involving 37,485 individuals at increased risk of cardiovascular disease. The analyses involved intention-to-treat comparisons of first events during the scheduled treatment period. There were 9326 major vascular events (3990 major coronary events, 1528 strokes and 5068 revascularizations), 3010 cancers and 5125 deaths. Folic acid allocation yielded an average 25% reduction in homocysteine levels.

 

During a median follow-up of 5 years, folic acid allocation had no significant effects on vascular outcomes. Dietary supplementation with folic acid to lower homocysteine levels had no significant effects within 5 years on cardiovascular events or on overall cancer or mortality in the populations studied, researchers concluded.