Distribution of serum concentrations of -tocopherol and -tocopherol in the US population

Background: Although the population distribution of serum concentrations of -tocopherol has been described in the United States, little is known about the distribution of -tocopherol or the ratio of -tocopherol to -tocopherol. Objective: Our aim was to describe the distribution of serum concentrations of -tocopherol and -tocopherol in a nationally representative sample of US adults. Design: We reviewed data from 4087 adults aged 20 y who participated in the National Health and Nutrition Examination Survey (1999–2000). Concentrations of -tocopherol and -tocopherol were measured by using HPLC with ultraviolet-visible wavelength detection. Results: The arithmetic mean ( SEM) of serum concentrations of -tocopherol was 30.09 0.45 mol/L, the median was 25.94 mol/L, and the geometric mean ( SEM) was 27.39 0.38 mol/L. The arithmetic mean of serum concentrations of -tocopherol was 5.74 0.22 mol/L, the median was 5.25 mol/L, and the geometric mean was 4.79 0.18 mol/L. The median ratio of -tocopherol to total cholesterol was 4.93 mol/mmol, that of -tocopherol to total cholesterol was 1.03 mol/mmol, and that of -tocopherol to -tocopherol was 4.53 mol/mmol. Concentrations of -tocopherol increased significantly (P for trend 0.001) with age and were significantly (P 0.015) lower in men than in women. African Americans and Mexican Americans had significantly (P 0.001) lower concentrations of -tocopherol than did whites. The median concentrations of -tocopherol showed a trend with respect to age, did not differ significantly between men and women, and were slightly but nonsignificantly lower in white participants than in African American or Mexican American participants. Conclusion: Sociodemographic variations in serum concentrations of -tocopherol and -tocopherol exist among US adults. Am J Clin Nutr 2006;84:375–83.