The relationship between plasma alpha-tocopherol concentration and vitamin E intake in patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (DM2) predisposes to an increased production of free radicals and a probable reduction in plasma antioxidants, including vitamin E. This cross-sectional study investigated the relationship between plasma alpha-Tocopherol concentration and vitamin E intake in 58 Brazilians with DM2. Plasma alpha-Tocopherol was determined by high-performance liquid chromatography. The intake of vitamin E-rich foods was assessed by a food frequency questionnaire. Total cholesterol and fractions were measured by colorimetric enzymatic methods. Data on demographic and socioeconomic factors, life habits, and anthropometry were obtained by a questionnaire and physical examination. The association between plasma alpha-Tocopherol and vitamin E intake was assessed by multiple linear regression analysis. The following variables were included in the regression model: alpha-Tocopherol, vitamin E intake, total cholesterol and fractions, body mass index, waist circumference, gender, age, education, occupation, income, smoking, alcohol intake, and blood pressure. There was no association between alpha-Tocopherol and vitamin E intake, but there were significant associations between alpha-Tocopherol and total cholesterol (p < 0.001) and waist circumference (p = 0.003). There were 36.2 % diabetics with low alpha-Tocopherol concentrations (< 12 µmol/L) and 32.7 % with a low alpha-Tocopherol/total cholesterol ratio (< 2.2). Further large, epidemiological, longitudinal studies, including measurements of gamma-tocopherol in blood, should be conducted to confirm our results.