Vitamin E is a tocopherol that functions as an antioxidant, protecting the integrity of lipid membranes and preventing oxidative damage to retinol. Vitamin E deficiency can be caused by conditions that cause fat malabsorption such as cholestatic liver disease, pancreatic insufficiency and small intestinal resection or disease. Deficiency of Vitamin E in adults and children causes reversible neuropathy and hemolysis..
Specimen requirement is a red top tube of blood. Patient should be fasting overnight to prevent falsely elevated concentrations. Vitamin E is measured in serum by liquid chromatography combined with tandem mass spectrometry.
Vitamin E levels below 5.0 ug/mL are considered deficient. Levels greater than 40 mg/L indicate excessive vitamin E.