DHEA is a steroid hormone produced by the adrenal glands. Often called "the mother steroid" because it can be converted into testosterone and estrogen, DHEA circulates throughout the body in the bloodstream, primarily in the sulfated form DHEA-S. DHEA is the most abundantly produced adrenal steroid. Serum concentrations of DHEA-S are approximately 20 times higher than those of any other steroid hormone. The body's ability to produce DHEA declines with age, with peak serum DHEA and DHEA-S levels occurring around age 25 and decreasing thereafter. By age 90, DHEA levels in the body are roughly 5% of what they were at their peak. Although the physiological role of DHEA is unknown, many scientists believe the decline of DHEA production by the adrenals may contribute to the physical and mental deterioration associated with aging. Synthetic DHEA is available in capsule form, most commonly in 10, 25, and 50 mg sizes. DHEA may also be purchased in creams, ointments, and lozenges.
Although there is no known toxicity for DHEA, safe daily intake levels vary with the hormonal profile of the individual. Long-term evidence of safety is lacking. Because DHEA supplements can increase levels of certain male and female hormones, some scientists believe excess DHEA consumption may contribute to certain hormone-dependent cancers. For this reason, it is recommended that DHEA only be supplemented by people with low levels of the hormone, and only under the supervision of a physician who can monitor hormonal changes. Side-effects associated with elevated DHEA levels include acne, growth of excess facial hair and deepening of the voice in women, over-stimulation or insomnia, and fatigue. These effects are generally seen in higher doses (over 50 mg) and are uncommon at lower doses (5 to 25 mg).