Effects of elevated d-alpha(RRR)-tocopherol dosage in man.
A study was conducted to investigate the effects of a megadosage of free RRR-alpha-tocopherol in healthy college student volunteers. Of 19 volunteers, 14 were given daily doses of 600 mg (900 IU) of RRR-alpha-tocopherol for 12 weeks, and the remaining 5 were given identical placebo capsules. The investigation was performed by the single-blind method. Alpha-tocopherol levels were measured in plasma, red blood cells (RBCs), platelets, leucocytes (WBCs), and buccal mucosal cells. Alpha-tocopherol in plasma, RBCs, and WBCs rose, reached a maximum level 4 weeks after commencement of administration, and then remained at a plateau, while platelet and buccal cell levels reached a maximum level after 12 weeks of administration. The maximum levels in all the subjects were 2.5 to 3 times the baseline values. During the study, there were no changes in laboratory values for thyroid, liver, or kidney functions, and coagulation activity (including the vitamin K-dependent Hepaplastin test and PIVKA-II) or immunoglobulin levels. Healthy status continued without any abnormal symptoms, and without any subjective complaints on the questionnaire. In the control group also, no changes occurred during the investigation. Gamma-tocopherol changes were measured in plasma and RBCs. As plasma and RBC tocopherol levels rose after administration, the isomer levels were suppressed in both plasma and RBCs.
Kitagawa
M
M
Department of Pediatrics, Osaka Medical College, Japan.
Mino
M
M
D000328:Adult; D001682:Biological Availability; D001772:Blood Cell Count; D001774:Blood Chemical Analysis; D006801:Humans; D008297:Male; D014810:Vitamin E / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood
D014810:Vitamin E