Methylenetetrahydrofolate reductase 677C→T genotype modulates homocysteine responses to a folate-rich diet or a low-dose folic acid supplement: a randomized controlled trial

摘要: Background: Low folate status and elevated plasma homocysteine are associated with increased risk of neural tube defects cardiovascular disease. Homocysteine responses to may be influenced by genetic variants in metabolism. Objective: We determined the effect folate-enhancing dietary interventions on total (tHcy) respect methylenetetrahydrofolate reductase 677C→T genotype. Design: A 126 healthy subjects (42 TT, 42 CT, CC genotypes) completed 3 (4 mo each) random order: 1) exclusion diet (avoidance folic acid–fortified foods ingestion a placebo daily), 2) folate-rich (increased intake fortified naturally achieve 400 μg folate/d), 3) supplement (exclusion plus μg/d). Results: Plasma was higher (P ≤ 0.001) tHcy lower after than diet. significantly greater supplementation diet, but there no significant difference concentration = 0.72). TT homozygotes had (14.5 compared 8.9 μmol/L, P (14.8 19.0 nmol/L, 0.01) did genotype CT heterozygotes intermediate concentrations. The trend toward persisted throughout study less marked increasing (TT supplementation, 0.097). Conclusions: including or low-dose supplements effectively increases status. require intakes do individuals similar concentrations responsive intervention.