Most commercial Vitamin E consists of only the α-tocopherol (alpha-tocopherol) form, while it has been recognized that the β- (beta) and γ-tocopherol (gamma tocopherol) forms are also important for human physiology. This paper presented by researchers at the Johns Hopkins University School of Public Health documents that taking α-tocopherol by itself can cause a deleterious deficiency state of the other forms. This explains some the contradictory findings of earlier studies on Vitamin E. Mixed tocopherol forms are available.