Human adipose alpha-tocopherol and gamma-tocopherol kinetics during and after 1 y of alpha-tocopherol supplementation.

Alpha-tocopherol and gamma-tocopherol were monitored in human adipose by using needle biopsies in four subjects during a 1-y supplementation trial with 800 mg all-rac-alpha-tocopherol/d, and for 1 additional year after cessation of supplement. Some increase in adipose alpha-tocopherol (per milligram adipose cholesterol) and a more consistent decrease in gamma-tocopherol were observed during the supplementation period. The alpha-tocopherol/gamma-tocopherol ratio rose consistently during supplementation and fell only gradually after the supplement was stopped. We estimate that > or = 2 y are required for the alpha-tocopherol/gamma-tocopherol ratio to reach a new steady state after a change in alpha-tocopherol intake. In a cross-sectional measurement in five subjects who reported long-term use of alpha-tocopherol supplements (> or = 250 mg/d), and in five other subjects who reported no supplement use, the adipose alpha-tocopherol/gamma-tocopherol ratio clearly discriminated between the two groups (P < 0.002). This ratio may be of value in ranking individuals according to long-term alpha-tocopherol intake.