Consumers can buy DHEA and melatonin over the counter, resulting in widespread use unsupervised by physicians. With the exception of testosterone and estrogen, researchers have not had time to complete the carefully controlled, long-term studies that are needed to show how these hormone supplements affect people over time. Testosterone, estrogen, and hGH are available by prescription only, and in cases of genuine deficiency, have been shown to confer important health benefits when taken under a doctor's supervision. However, unsupervised use of any hormone supplement can lead to health problems. DHEA supplements may affect the body in some of the same ways as testosterone and estrogen.
Hormones are powerful chemicals produced by glands.
Whether made internally by glands or taken externally as supplements, hormones enter the bloodstream and travel throughout the body. Tiny amounts of hormones may have far-reaching effects. Several NIA-funded studies of hormone supplements are under way. The NIA leads the Federal effort supporting medical and social research on aging and the special needs of older people.