Distribution of serum concentrations of α-tocopherol and γ-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 -tocopherolwas5.740.22mol/L,themedianwas5.25mol/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 -tocopherolto-tocopherolwas4.53mol/mmol.Concentrations of -tocopherol increased significantly (P for trend 0.001) with ageandweresignificantly(P0.015)lowerinmenthaninwomen. 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 wereslightlybutnonsignificantlylowerinwhiteparticipantsthanin 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.