What is DHEA?
DHEA is the most abundant steroid hormone in our bodies. (Hormones in this category include estrogen, testosterone, and cortisone.) DHEA, short for dehydroepiandrosterone, can convert to either testosterone or estrogen; it reaches its peak when we're in our 20's and then performs a dramatic disappearing act as we age.
After we hit 30, our DHEA levels drop about 10 percent every 10 years. Nobody knows why the hormone declines with age or even whether the drop is harmful or helpful. Scientists see two rather contradictory possibilities: Either our bodies make less DHEA as a defense against aging or the DHEA shortage causes many of aging's effects.
Option number two has made DHEA popular among researchers as well as a phenomenon in the dietary supplement industry. Researchers have investigated DHEA's role in cardiovascular disease, diabetes, aging, cancer, osteoporosis, AIDS, arthritis, autoimmune diseases, and other illnesses. The evidence is not conclusive, however, and long-term studies of the drug have not been done on humans. For these reasons, even researchers optimistic about DHEA's possible value warn that the hormone should be used with caution and its users monitored closely for harmful side effects.
Despite the lack of long-term studies, some supplement makers have promoted as an anti-aging cure-all that can increase energy, improve sex drive, build muscle, burn fat, enhance mood, and boost the immune system while preventing cancer, heart disease, diabetes, and Alzheimer's. As is often the case with supplements, however, far more promises -- and profits -- surround DHEA than actual proof.
Does DHEA really work?
DHEA certainly has the power to revolutionize the field of rodent health. In rats, mice, and other laboratory animals, DHEA supplements promote fat loss, improve memory, bolster the immune system, and help ward off cancer, hardening of the arteries, and diabetes. Of course, rats and mice aren't always good role models for humans. These animals produce much less DHEA than we do, and the amount doesn't decline with age. While some researchers think that DHEA has the potential to treat various illnesses, so far there's little reason to think that DHEA supplements would have the same effects on mice and men.
Scientists have conducted a few small short-term studies of human use of DHEA with mixed results. While one study found that subjects who took 50 milligrams of DHEA for 12 weeks reported an enhanced sense of well-being, several other studies found neither this change nor any improvement in mood or cognitive performance. Some small studies do show DHEA can increase skin thickness, skin hydration, and decrease facial pigmentation. And taking DHEA orally for 24 weeks seems to improve sexual drive, function, and satisfaction in men. A number of other studies though suggest that DHEA supplements have no effect on a person's weight or body fat, bone mineral density, or muscle strength.
DHEA also shows limited promise as a disease fighter. One study found that 200 mg of DHEA a day eased the symptoms of women with systemic lupus, according to a study from the Stanford University Medical Center; some evidence also indicates that the supplement boosts at least some elements of the immune system. But the hormone doesn't seem to protect against diabetes; in fact, high doses given to postmenopausal women can actually make them resistant to insulin (a stage that often precedes a diabetes diagnosis).
Some research suggests that low DHEA is linked to heart disease, rheumatoid arthritis, and other illnesses. Studies so far have been too brief to show whether DHEA can prevent or slow the progression of heart disease or cancer, but many experts are skeptical that it can. The role of the hormone in heart disease is unclear, and people with naturally high levels may actually face a greater-than-average risk for cancer.
Are DHEA supplements dangerous?
Nobody knows the long-term risks of taking DHEA, but there's no question that the stuff can throw your hormones out of balance. A single small dose of DHEA greatly (though temporarily) increases the levels of testosterone in women and estrogen in men. Women who take more than 100 mg a day risk developing facial hair, a deeper voice, and acne.
Other possible effects could be extremely serious. As noted earlier, naturally high levels of DHEA seem to promote certain types of cancer. Specifically, experts at the Mayo Clinic worry that DHEA supplements could increase the risk of prostate cancer in men and breast and ovarian cancer in women.
In conclusion, the proven benefits are few, if any, and the risks are very real. Talk with your doctor if you want to experiment with the supplement. For now, sticking with your natural allotment of DHEA seems the safest way to go.
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Natural Medicines Comprehensive Database. DHEA.