The most abundant hormone found in the bloodstream, dehydroepiandrosterone (DHEA) is produced by the adrenal glands, which sit atop the kidneys. Much like human growth hormone (HGH) and melatonin-two other hormones now known to have anti-aging properties-DHEA is produced abundantly during youth, with production peaking around age twenty-five. After this, though, production wanes. By the age of eighty, people are thought to have only 10 to 20 percent of the DHEA they had at twenty.
Research has shown that DHEA has many functions in the body pertaining to health and longevity. Among other things, it helps to generate the sex hormones estrogen and testosterone; increases the percentage of muscle mass; decreases the percentage of body fat; and stimulates bone deposition, thereby helping to prevent osteoporosis. As the production of DHEA declines with age, the structures and systems of the body appear to decline with it. This leaves the body vulnerable to various cancers, including cancer of the breast, prostate, and bladder, as well as to atherosclerosis, high blood pressure, Parkinson’s disease, diabetes, nerve degeneration, and other age-related conditions.
Research suggests that DHEA replacement therapy can have a number of highly beneficial effects. In a 1986 study based on twelve years of research involving 242 middleaged and elderly men, small doses of DHEA appeared to be linked with a 48-percent reduction in death from heart disease, and a 36-percent reduction in death from other causes. In a twenty-eight-day study, DHEA therapy enabled men to lose 31 percent of mean body fat without changing body weight. DHEA is thought to have caused this loss of fat by blocking an enzyme that is known to produce fat tissue and promote cancer cell growth. In another study, middle-aged and elderly men taking DHEA for one year experienced a markedly greater sense of well-being, including a better ability to cope with stress, increased mobility, decreased pain, and higher quality sleep. Research also indicates that DHEA supplements can help prevent cancer, arterial disease, multiple sclerosis, and Alzheimer’s disease; treat lupus and osteoporosis; enhance the activity of the immune system; and improve memory. Laboratory studies in animals have indicated that DHEA can increase lifespan by as much as 50 percent.
DHEA comes both in nonprescription-strength pills and capsules, and in higher-dosage prescription-strength pills and capsules. Most of the DHEA that you can buy is made in laboratories from substances extracted from wild yams, the most common substance being diosgenin. Also available are extracts of the wild yams that have not been processed into DHEA, but which the body may convert into DHEA.
DHEA therapy should be undertaken with caution. Some physicians believe that high doses of DHEA suppress the body’s natural ability to synthesize the hormone. Women should take no more than 10 milligrams daily. Animal studies have indicated that high doses can also lead to liver damage. For this reason, while undergoing DHEA replacement therapy, it is important to take supplements of the antioxidants vitamin C, vitamin E, and selenium to prevent oxidative damage to the liver. 7-Keto DHEA may be a better source of DHEA than ordinary DHEA. 7-Keto DHEA plays the same role as DHEA in the body, such as strengthening the immune system and enhancing memory, but, unlike ordinary DHEA, it is not converted into estrogens or testosterone.