Alcohol increases homocysteine and reduces B vitamin concentration in healthy male volunteers—a randomized, crossover intervention study

Background: Few studies have examined the effect of alcohol consumption on total homocysteine (tHcy) concentrations. Aim: To assess the effect of an 8-week intervention with vodka or red wine on plasma tHcy and B vitamin concentrations in healthy male volunteers. To assess the effect on tHcy according to methylenetetrahydrofolate reductase (MTHFR) 677C>T genotype. Design and methods: A randomized controlled crossover intervention study measuring tHcy and serum folate and vitamin B12 concentrations was conducted in 78 male subjects (21–70 years). Following a 2-week washout period during which no alcohol was consumed, all subjects consumed 24 g alcohol (either 240 ml red wine or 80 ml vodka)/day for a 2-week period. Following a further 2-week washout, participants consumed the alternate intervention for 2 weeks. Results: A significant increase in plasma tHcy was observed after the 2-week red wine intervention (5%, P = 0.03), and a non-significant increase in tHcy with vodka intervention (3%, P = 0.09). When the two interventions were compared, the change in tHcy did not differ between the vodka and red wine interventions (P = 0.57). There were significant decreases in serum vitamin B12 and folate concentrations, and this decrease did not differ between interventions. The increase in tHcy observed in both interventions did not vary by MTHFR 677C>T genotype. Conclusions: A 2-week alcohol intervention resulted in a decrease in folate and vitamin B12 status and an increase in plasma tHcy. The effect of alcohol intervention on tHcy, folate and vitamin B12 concentrations did not differ between the red wine and vodka intervention groups.