DHEA: Unraveling The Mystery
For: Wellness Facts,
October 2003
"Promising," "tantalizing, "interesting"—that's how many scientists describe DHEA, the mystery hormone that's for sale as a "dietary supplement" in most drugstores and health-food stores. It's promoted as a "clinically proven fountain of youth" and a panacea in ads and catalogues and on the Internet. At the same time, many of these same scientists look upon the sale of DHEA pills as alarming—"a recipe for disaster," in the words of Dr. Peter Casson of Baylor College of Medicine in Houston. Dr. John Renner of the University of Missouri School of Medicine in Kansas City, quoted in the Journal of the American Medical Association, cautions against taking DHEA. But if you do take it, he suggests that you keep track of the batch number, save the last five pills from each bottle, and buy only from a large health-food store chain that can "afford to be sued in case of adverse reactions."
We think you should avoid DHEA and not worry about lawsuits. This was our advice three years ago, and nothing has emerged to change our minds. But here's an update, in case you've recently tuned in to DHEA.
DHEA (dehydroepiandrosterone) is a hormone manufactured in the human adrenal gland; other primates also produce it. DHEA-sulfate, or DHEAS, is a related form of the hormone. There's more DHEAS circulating in the body than any other hormone. It's a "precursor" hormone—that is, it is a basic chemical that the body uses for different purposes. It can be converted to androstenedione, and then to testosterone or estrogen. Production begins in the fetus, stops at birth, resumes around age 7, peaks at about age 25, and then begins to decline. By age 70 production falls to one-fifth or as low as one-twentieth of what it was at age 25. If a hormone goes along with youth and vigor and then almost disappears, it's logical to wonder whether it might prevent or slow aging as well as the chronic diseases of aging. But DHEA, discovered in the 1930s, does not easily yield its secrets.
Research so far: mostly confusion
Most of the studies so far have been with lab animals, chiefly rodents. This is a drawback because rodents produce negligible amounts of DHEA, and the results in rodents probably don't apply to humans. In any case the results have been unclear: sometimes DHEA seems to improve rodent immunity or confer other benefits, while in other studies DHEA appears to cause cancer. Studies of humans have also yielded confusing results. It's much too early, most scientists think, to launch big clinical trials, since so little is known about the basic biology of DHEA. No one even understands what it does in adults, except that it affects many bodily systems.
At least 21 studies of DHEA have been done in people, using widely varying doses and administered either by injection or orally. Researchers are interested in its possible effects on the cardiovascular, immune, digestive, and nervous systems—and in whether it promotes or protects against tumor growth, as well as obesity. But no answers have been forthcoming. Studies of DHEA and immunity in older people have had disappointing results. An early study found that high blood levels of DHEA are associated with a lower risk of heart disease—in men but not women—but this is far from definite. Other studies suggest that high natural levels of DHEA are linked to a lower risk of breast cancer in premenopausal women, but to a higher risk in postmenopausal women. As reported in the Journal of the National Cancer Institute in September, a study found that postmenopausal women with the highest blood levels of DHEAS (occurring naturally, not administered experimentally or as a supplement) had the highest risk of breast cancer.
But studies continue, here and in other countries. DHEA might prove useful against such immune-system disorders as lupus or AIDS. It might slow aging. On the other hand, it may prove to promote cancer. Little is known about lesser side effects, which in women may include the growth of unwanted facial hair, male-pattern baldness, deepening voice, and acne.
It's not possible to say of DHEA, as is often said of various herbal remedies, "it's widely used in other countries." No country with a regulatory system for drugs allows DHEA to be sold over the counter. In Canada it is not available even by prescription. In the United Kingdom it is available on a limited basis by prescription only, but there are no approved uses. In Italy it is in wide use, apparently, but only by prescription.
But is it really DHEA?
DHEA is a substance so poorly understood and so potent that you may wonder how it can be sold as an unregulated product. Would you want to buy over-the-counter testosterone, another potent hormone that may cause cancer in large doses? Some women do take estrogen, of course, but only by prescription and only after consultation with a physician. And as we reported in December, hormone replacement therapy (HRT) is by no means advisable for all women. But whatever the drawbacks of HRT, it is one of the most intensively studied treatments in modern medicine. At least there's a body of knowledge on the subject.
Because of the U.S. Dietary Supplement Health and Education Act of 1994, which relaxed the rules for "dietary supplements," DHEA can be sold without testing, so long as the label makes no specific medical claims. DHEA doesn't even exist in foods, except in the adrenal glands of monkeys and other primates, which are not sold for human consumption.
To add to the confusion—and perhaps it's a lucky break for the public—what's sold as DHEA may not be DHEA. Our bodies synthesize DHEA from cholesterol, but what's sold over the counter is synthesized from plants (which don't contain any cholesterol). Wild yam extracts and soy do contain substances that can be converted into human hormones such as DHEA and cortisone, but only by a long, complex manufacturing process. Scientific investigators require (and get) a product that's pure and consistent—the real thing. However, the wild yam extracts billed as DHEA in stores are plant products that the body can't convert to DHEA or any other hormone. Even if the product you buy does contain real DHEA, there's no guarantee it has the amount claimed on the label.
Last words: DHEA is not a "natural medicine" and not a dietary supplement—and how the FDA could allow it to be classified as such remains a mystery. What's currently on the market is probably a complete waste of money. If this supplement really works like a hormone, then it's risky business. The only certain benefit is a profit for those who sell it.
UC Berkeley Wellness Letter, February 1999
