Serum homocysteine, B12 and folic acid concentration in Thai overweight and obese subjects.

This study investigated levels of serum homocysteine, vitamin B12, folic acid, vitamin B6 and vitamin C, in 37 male and 112 female overweight and obese Thai volunteers (body mass index; BMI > or = 25.00), and 23 male and 90 female normal-weight Thai volunteers, who came for a physical check-up at the Out-patient Department, General Practice Section, Rajvithi Hospital, Bangkok from March to October of 2000. Data included anthropometric measurements and waist/hip ratios. All anthropometric variables, except height, were significantly higher for the overweight subjects than for the normal subjects. Statistically significantly higher levels of serum homocysteine were found in the overweight subjects. Serum homocysteine concentrations in overweight and obese males were significantly higher than in overweight and obese females. Serum folic acid and vitamin C in the overweight and obese were found to be statistically significantly lower than in the control subjects. No statistically significant difference in vitamin B12 was found in the overweight and obese subjects compared with the normal control subjects. The medians of serum folic acid and vitamin C concentrations for the overweight and obese males were significantly lower than those of the overweight and obese females. A negative correlation was found between serum folic acid and homocysteine concentrations in all overweight and obese subjects. A significant negative correlation between serum folic acid and vitamin B6 was observed in both male and female overweight and obese subjects. The results of the investigation suggest that homocysteine levels in overweight and obese subjects seem to be caused by insufficient dietary folic acid intake and probably not by B12 deficiency.