Dehydroepiandrosterone: A Nutritional Supplement with Actions in the Central Nervous System

Because of changes wrought by the U.S. Dietary Supplement Health and Education Act of 1994, DHEA (dehydroepiandrosterone) is now available to the general population as a dietary supplement. Although advertising of any health benefit is restricted, many people take it for purported salutary effects of age-related processes. One of these suspected benefits is the delay of Alzheimer's disease. This review evaluates the literature derived from both animal and human trials that leads people to believe DHEA may exert such an effect. It will show that DHEA is active in the central nervous system when given exogenously, is made in the central nervous system of laboratory animals and may have a role in regulating normal physiologic processes. Possible cellular mechanisms of action are described. DHEA may have particular effects on learning and memory in test animals, but there is only sparse data in humans where observations are indirect and poorly controlled. Still, it is concluded that the data is compelling enough to warrant further research, although it is premature to suggest a safe dosing schedule for humans who may want to try this steroid hormone.