Graduation date: 2008In rats, sesame lignans increase plasma γ-tocopherol concentrations and inhibit γ-tocopherol degradation to its metabolite γ-carboxyethylhydroxychroman (γ-CEHC). To test if sesame lignan consumption inhibits γ- tocopherol metabolism in humans, muffins prepared with either corn oil (control) or sesame oil and an equimolar mixture of deuterium labeled d6-α- and d2-γ- tocopheryl acetates were administered to male (n=5) and female (n=5) volunteers. Tocopherol and CEHC concentrations were followed for 72 h. Sesame lignan consumption significantly increased plasma d2-γ-TOH concentrations (p<0.05). In men, sesame lignans increased plasma d2-γ-tocopherol areas under the curve (AUC; sesame oil: 34.3 ± 4.6; corn oil: 28.9 ± 3.3 μmol/L·h, p<0.01) and reduced d2-γ-CEHC AUCs (p<0.05). In men, differences in urinary d2-γ-CEHC AUCs did not reach statistical significance (AUCs for 24 h, corn oil: 11.2 ± 3.0 μmol/g creatinine·h; vs sesame oil: 5.0 ± 1.5). In women, sesame lignan consumption did not alter plasma tocopherol CEHC concentrations but reduced urinary d2-γ-CEHC excretion (AUCs for 24 h, corn oil: 19.3 ± 4.9 μmol/g creatinine·h; and sesame oil: 7.7 ± 2.0, p < 0.05). These data suggest that sesame lignans alter γ-tocopherol metabolism differently in men and women. Further research is needed to assess the mechanism involved in these differences.