Volume 89, Issue 3, March (2003), pp. 295-301 © The Author 2003
doi:10.1079/BJN2002776

Plasma homocysteine concentration is decreased by dietary intervention^*

Marja-Leena Silaste^1,CA, Maire Rantala¹, Georg Alfthan², Antti Aro² and Y. Antero Kesäniemi¹
SUP>1Department of Internal Medicine and Biocenter Oulu, University of Oulu, Kajaanintie 50, P.O. Box 5000, FIN-90014 Oulu, Finland
²National Public Health Institute (KTL), Mannerheimintie 166, FIN-00300, Helsinki, Finland

 (Received 19 November 2001–Revised 17 September 2002–Accepted 30 September 2002)

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 B₁₂, 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 B₁₂ remained unchanged during the intervention. The mean plasma tHcy concentration was 8·0mmol/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.

Abbreviations: RBC; erythrocyte; tHcy; total homocysteine

Keywords:
Diet, Folate, Homocysteine