Plasma homocysteine concentration is decreased by dietary intervention

Abstract

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 frui/, while during the high-folate diet the subjects ate at least seven servings of vegetables, berries, and citrus frui/. 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) nmo/ and 412 (sd 120) nmo/ 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 μmo/ 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.