 The liver recognizes and preferentially re-secretes α-tocopherol into circulation, making it the most abundant vitamer of vitamin E in the blood.While tocotrienols are present in lower concentrations, they have more potent antioxidant properties than α-tocopherol and can have metabolic impacts at low concentration.Normal serum concentrations of α-tocopherol in adults ranges from 5 to 20 μg/mL.