Plasma homocysteine concentration is decreased by dietary intervention

High plasma total homocysteine (tHcy) concentration is reported to be a risk factor for vascular diseases. We investigated the extent to which serum folate and plasma tHcy respond to a high intake of natural folate from food. Thirty-seven healthy females volunteered to participate in a crossover dietary intervention. The study included a baseline period and two 5-week diet periods (low- and high-folate diets) with a 3-week washout in between. The low-folate diet contained one serving of both vegetables and fruit/d, while during the high-folate diet the subjects ate at least seven servings of vegetables, berries, and citrus fruit/d. Serum and erythrocyte (RBC) folate, serum vitamin B-12, and plasma tHcy concentrations were measured at the baseline and at the end of each diet period. The mean concentrations of serum and RBC folate were 11.0 (sd 3.0) nmol/l and 412 (sd 120) nmol/l at the end of the low-folate diet and 78 (95 % CI 62, 94) % and 14 (95 % CI 8, 20) % higher in response to the high-folate diet (P<0.001). The serum concentration of vitamin B-12 remained unchanged during the intervention. The mean plasma tHcy concentration was 8.0 µmol/l at the end of the low-folate diet and decreased by 13 (95 % CI 9, 18) % in response to the high-folate diet (P<0.001). In conclusion, a diet high in fresh berries, citrus fruit, and vegetables effectively increases serum and RBC folate and decreases plasma homocysteine. Reprints: