Alpha-tocopherol

Vitamin E/Nutrient Depletion:

  • Alpha-tocopherolAlpha-tocopherol: According to review data, high doses of alpha-tocopherol may deplete levels of gamma-tocopherol in the tissue in plasma (4).
  • AnticonvulsantsAnticonvulsants: In human research, anticonvulsant drugs such as phenobarbital, phenytoin, or carbamazepine have been shown to decrease blood levels of vitamin E in handicapped patients (130; 131).
  • AntilipemicsAntilipemics: In humans, simvastatin has been reported to decrease levels of alpha-tocopherol significantly (170). In humans, cholestyramine has been shown to reduce dietary vitamin E absorption and blood levels of vitamin E, as well as vitamin E levels in LDL (136; 137). However, this effect was not observed in a trial of cholestyramine combined with statins (138). In humans, colestipol has been shown to reduce dietary vitamin E absorption and blood levels of vitamin E (139; 140).
  • AntineoplasticsAntineoplastics: In human research, a transient decrease in alpha-tocopherol in erythrocyte membranes and an increase in alpha-tocopherol in lipoprotein fractions has been associated with letrozole therapy for four months (142). In human research, a significant decrease in serum alpha-tocopherol was observed in non-small cell lung cancer patients treated with gefitinib (143).
  • Antituberculosis agentsAntituberculosis agents: Antituberculosis drugs such as isoniazid have been shown to cause liver injury (144). In theory, use of isoniazid may reduce dietary vitamin E absorption and blood levels of vitamin E due to the liver's involvement in vitamin E kinetics.
  • Aromatase inhibitorsAromatase inhibitors: In human research, a transient decrease in alpha-tocopherol in erythrocyte membranes and an increase in alpha-tocopherol in lipoprotein fractions have been associated with letrozole therapy for four months (142).
  • Bile acid sequestrantsBile acid sequestrants: In human research, cholestyramine has been shown to reduce dietary vitamin E absorption and blood levels of vitamin E, as well as vitamin E levels in LDL (136; 137). However, this effect was not observed in a trial of cholestyramine combined with statins (138). In human research, colestipol has been shown to reduce dietary vitamin E absorption and blood levels of vitamin E (139; 140).
  • CigarettesCigarettes: In human research, cigarette smokers showed significant lowering of alpha-tocopherol levels in plasma (158).
  • CopperCopper: In patients with G6PD deficiency, vitamin E supplementation has been shown to normalized elevated copper levels associated with the disease (159).
  • Gamma-tocopherolGamma-tocopherol: According to a review, alpha-tocopherol supplements have been shown to lower levels of gamma-tocopherol in the blood (9).
  • GefitinibGefitinib: In human research, a significant decrease in serum alpha-tocopherol was observed in non-small cell lung cancer patients treated with gefitinib (143).
  • GemfibrozilGemfibrozil: In human research, gemfibrozil has been shown to decrease serum levels of both alpha- and gamma-tocopherol, although the clinical significance of this is not clear (149).
  • GlucoseGlucose: Vitamin E has been proposed for the prevention of types 1 or 2 diabetes and for the improvement of abnormal sugar control in diabetes (20; 21; 22). However, in a systematic review and meta-analysis, vitamin E was reported to increase insulin resistance (36). In another systematic review, it was reported that two participants treated with vitamin E developed new-onset diabetes, while all participants receiving placebo or pioglitazone did not develop diabetes (76).
  • IsoniazidIsoniazid: In theory, use of isoniazid may reduce dietary vitamin E absorption and blood levels of vitamin E due to the liver's involvement in vitamin E kinetics.
  • LetrozoleLetrozole: In human research, a transient decrease in alpha-tocopherol in erythrocyte membranes and an increase in alpha-tocopherol in lipoprotein fractions have been associated with letrozole therapy for four months (142).
  • Mineral oilMineral oil: According to secondary sources, mineral oil may reduce dietary vitamin E absorption.
  • Omega-6 fatty acidsOmega-6 fatty acids : According to secondary sources, increased intake of omega-6 fatty acids may increase vitamin E requirements, particularly at high doses.
  • OlestraOlestra: Although human research is mixed, olestra may reduce dietary vitamin E absorption and blood levels of vitamin E (166; 167; 168).
  • OrlistatOrlistat: In human research, orlistat has been shown to reduce dietary vitamin E absorption and blood levels of vitamin E (151; 152; 153; 154).
  • Stanyl estersStanyl esters: Stanyl esters have been proposed to reduce the absorption of fat-soluble vitamins. In human research, stanyl esters dissolved in margarine did not significantly affect the absorption of alpha-tocopherol (161).
  • SucralfateSucralfate: According to secondary sources, sucralfate may reduce dietary vitamin E absorption and blood levels of vitamin E.
  • Vitamin AVitamin A: Large doses of vitamin E may deplete vitamin A stores (86).
  • Vitamin KVitamin K: In adults not taking anticoagulants, high-dose vitamin E caused an increase in PIVKA-II (protein induced by vitamin K absence), indicating poor vitamin K status (163).