Adrenal disease? Dhea is the precursor to sex hormones (estrogen and testosterone). Testosterone is also released by the testes, and estrogen is also released by the ovaries. Some have used dhea for premature ovarian failure to help libido in women. However, these are mostly off-label uses that poor-quality studies to back them. Other uses (memory, aging, muscles, etc) are not validated and can be unsafe.
Anyone. Dehydroepiandosterone (DHEA) is a precursor for androgens (e.g. testosterone) estrogens. Levels decrease after age 30. In 25-100mg/day dosing, it is taken for a variety of conditions. These include, low testosterone in men, to improve well being and sexuality in men and women, depression, Parkinsons, and myriad other diseases and conditions. Who can take it? Basically anyone.