title: Vitamin E inadequacy in humans: causes and consequences.
abstract: It is estimated that >90% of Americans do not consume sufficient dietary vitamin E, as α-tocopherol, to meet estimated average requirements. What are the adverse consequences of inadequate dietary α-tocopherol intakes? This review discusses health aspects where inadequate vitamin E status is detrimental and additional vitamin E has reversed the symptoms. In general, plasma α-tocopherol concentrations <12 μmol/L are associated with increased infection, anemia, stunting of growth, and poor outcomes during pregnancy for both the infant and the mother. When low dietary amounts of α-tocopherol are consumed, tissue α-tocopherol needs exceed amounts available, leading to increased damage to target tissues. Seemingly, adequacy of human vitamin E status cannot be assessed from circulating α-tocopherol concentrations, but inadequacy can be determined from “low” values. Circulating α-tocopherol concentrations are very difficult to interpret because, as a person ages, plasma lipid concentrations also increase and these elevations in lipids increase the plasma carriers for α-tocopherol, leading to higher circulating α-tocopherol concentrations. However, abnormal lipoprotein metabolism does not necessarily increase α-tocopherol delivery to tissues. Additional biomarkers of inadequate vitamin E status are needed. Urinary excretion of the vitamin E metabolite α-carboxy-ethyl-hydroxychromanol may fulfill this biomarker role, but it has not been widely studied with regard to vitamin E status in humans or with regard to health benefits. This review evaluated the information available on the adverse consequences of inadequate α-tocopherol status and provides suggestions for avenues for research.
authors.forename: Maret G
authors.initials: MG
authors.lastname: Traber
mesh_terms: D000818:Animals; D019587:Dietary Supplements; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007223:Infant; D039382:Maternal Nutritional Physiological Phenomena; D009752:Nutritional Status; D011247:Pregnancy; D014810:Vitamin E / Q000008:administration & dosage / Q000097:blood*; D014811:Vitamin E Deficiency / Q000097:blood* / Q000188:drug therapy*
chemical_list: D014810:Vitamin E