Phase III Study of the Effects of Folic Acid Supplementation on Serum Folate and Plasma Homocysteine in Older Adults: A Dose-Response Trial

Elevated levels of homocysteine may be a risk factor for coronary heart disease, stroke, and peripheral vascular disease. Folate is a type of B vitamin that occurs naturally in food. In nutritional supplements, folate is known as folic acid, and it has been shown to lower the concentration of homocysteine in blood. Folic acid supplements are a simple way for people to increase their folate intake, lower their homocysteine levels, and reduce their risk of developing heart disease. However, more research is required to determine the most effective dose of folic acid needed to lower homocysteine levels. The purpose of this study is to examine the effect that varying doses of folic acid have on folate levels and homocysteine concentration levels in older adults.

This 6-week study will enroll healthy adults over the age of 60 who do not currently take multivitamins or B-vitamins. At a screening visit, participants will complete questionnaires on medical history, demographics, and diet. Also, height and weight will be measured, and a blood collection will occur. At a baseline study visit, participants will be randomly assigned to receive either placebo or one of four doses of folic acid-100 mcg, 400 mcg, 1000 mcg, or 2000 mcg-to be taken once a day for 6 weeks. Participants will attend a final study visit at Week 6, at which time another blood collection will occur.