Dehydroepiandrosterone is the most abundant adrenal steroid. The average daily output for men is 31 mg. and 19 mg. for women.
Levels peak at puberty and are already declining by maturity.
Compared to other hormones like melatonin and cortisol, there is little circadian variation. DHEA's primary role is as a precursor for the sex hormones, i.e., testosterone and estrogen. DHEA may increase serotonin which in turn may be an explanation for its mood altering and anti-depressant effects experienced by some. This may also explain why DHEA has been reported to increase REM sleep. DHEA is low in postpartum depression, anorexia nervosa, and schizophrenia.