The body produces 5–8 mg of DHEA every day, mostly in the adrenal glands. DHEA is made from another steroid hormone, pregnenolone, which itself is made from cholesterol.[1] In humans, DHEA is the second most abundant steroid after its sulfate ester, DHEA-S.[2] Rather than DHEA levels, blood tests usually measure DHEA-S levels, which are about a hundred times higher and fluctuate less during the day.[1]
The secretion of DHEA or supplementation with DHEA leads to increased levels of DHEA-S, a hydrophilic storage form of DHEA that stays in circulation. DHEA is the form that is transported into the tissues to be converted into the sex hormones (e.g., androgens and estrogens). Both DHEA and DHEA-S decrease significantly with age, with people in their 70s having less than 20% of the peak DHEA-S levels of young adults.[2][3][4][5] Since DHEA and DHEA-S are the most abundant circulating steroids in the body, and they decline with age, there is speculation that supplementation with DHEA and/or DHEA-S may reduce age-related declines in health.[2][6]