DHEA: What is known About DHEA

DHEA Research

DHEA is up there with Melatonin as the miracle supplement of the moment. Available at health food stores, DHEA has been touted as an anti-aging supplement and potential treatment for lupus, multiple sclerosis, and AIDS. Since it is marketed as a food supplement, DHEA escapes the usual FDA testing requirement for drugs. DHEA (dehydroepiandrosterone) is a naturally occurring precursor of both androgenic and estrogenic steroids. It is synthesized largely by the adrenal gland. In men and women, blood levels of DHEA peak at age 20 and decrease thereafter. The few studies exploring the benefits of DHEA provide reasons to be hopeful, but they can only be considered preliminary. Furthermore, virtually all had a small number of participants. The best were summarized in a recent issue of The Medical Letter (11 October 1996), a physician publication without drug advertising.

Reduces Viral Load

At the International Conference on AIDS in Vancouver, a team of researchers reported a study of 20 HIV-infected people who had never taken anti-retroviral drugs. DHEA, 300 mg or 600 mg twice daily, produced reductions in viral load. (No placebos were given.) In a three-month study of 28 people with systemic lupus, 200 mg DHEA daily produced symptom improvements not shown among the people taking placebos. In a study of people with multiple sclerosis given DHEA (no placebos), they reported increased feelings of strength, stamina, and well-being, but no reduction in disability. In another study, men over age 50 with high blood levels of DHEA also had lower rates of heart disease. The same study showed no benefit to women.

Anti-Aging

The anti-aging claims for DHEA probably stem from the few preliminary studies of healthy older people. Forty healthy people, aged 40 to 70 years, were given 50 mg of DHEA daily or a placebo in a study that lasted six months. No benefit was noted by those taking placebos, but the majority on DHEA reported improvements in psychological and physical well-being. A 12-month study of 16 men and women taking 100 mg of DHEA daily produced similar results.

As with any new drug, the side effects profile for DHEA is yet to be fully understood. The Medical Letter warns of DHEA's potential for androgenic effects in women, such as acne, hair loss, hirsutism (excessive body and facial hair), and deepening of the voice. (Hirsutism and voice changes may be irreversible.) In men, DHEA holds the possibility of stimulating the growth of prostate cancer. Despite early indications of potential benefit, The Medical Letter comes to a negative conclusion: There is no convincing evidence that DHEA has any beneficial effect on aging or any disease. Patients would be well advised not to take it. The FDA hasn't received much in the way of bad news about DHEA, though the supplement has been on the market for years. Only a few reports have come in on DHEA, and none were severe, said a spokesman for the FDA's Center for Food Safety and Applied Nutrition.

UCSF STUDY FINDS DHEA BENEFITS CARDIOVASCULAR FUNCTION

DHEA (dehydroepiandrosterone), the popular hormone widely sold as a nutritional supplement to fight conditions from cancer to aging, does in fact have a beneficial effect on the vascular function of the heart, a new University of California San Francisco study shows. Though there has been limited scientific basis for claims that DHEA is a potent anti-disease and anti-aging drug, the new study, which will be presented today
(Nov. 10) at the American Heart Association Scientific Sessions in Dallas, shows that DHEA does protect the heart against some cardiovascular diseases.

Scientists suspect DHEA -- which is synthesized by our own bodies, is converted into the hormones estrogen and testosterone and decreases sharply with age -- does indeed have a link to conditions including aging, heart disease and cancer, said UCSF cardiology research fellow Christian Zellner, MD, who conducted the study under the direction of UCSF Stanford Health Care cardiologists Tony Chou, MD, UCSF assistant professor of medicine, and Kanu Chatterjee, MD, UCSF professor of medicine, at UCSF's Vascular Lab. Researchers at medical centers across the country are investigating a number of DHEA-related issues, including DHEA's role in brain diseases, including Alzheimer's disease, and autoimmune diseases, such as lupus. Some of the lingering questions also include why only humans and primates manufacture the hormone and why it diminishes sharply with age.

This study, part of UCSF's continuing research of DHEA's effects on cardiovascular health, is an important step in giving scientific credence to the role and benefits of DHEA, Zellner said. The research is also a step in understanding any possible untoward effects on individuals who take the drug with high hopes of beating aging and disease, Zellner said. That is important, he said, because an increasing number of people are taking DHEA, yet its sale is unregulated by the FDA. The animal study, conducted on pigs, shows that DHEA can reverse the effects of Endothelin-1, or ET-1, a peptide that is elevated in most heart diseases, including heart attacks and high blood pressure. A balance between ET-1 and nitric oxide is essential for maintaining vascular tone, which is necessary for controlling blood pressure, maintaining the tone of coronary arteries and regulating blood flow to the heart and other parts of the body, Zellner said.

When ET-1 is elevated the heart's vessels constrict, meaning the flow of blood is hampered and the heart's tissue does not get the oxygen and nutrients it needs to perform well and stay healthy. The study, however, found that DHEA reversed that vascular constriction and reestablished bloodflow. This year marks the third year in a row that UCSF's Vascular Lab, one of the few groups in the country researching DHEA's effects on heart disease, will present findings on the topic at the AHA conference. The UCSF group showed previously that DHEA dilates the coronary arteries in a similar way to anti-anginal drugs like nitroglycerin and increases the function of the endothelial cells, which create the inner lining of the arteries and offer protection against a wide range of cardiovascular disorders, including atherosclerosis.

Though DHEA has become increasingly popular as a nutritional supplement, there is still a lot of scientific work that needs to be done to make sure the hormone is both safe and beneficial, Zellner said. No human studies examining the cardiac effects of DHEA have been completed, which is essential before any recommendations involving the drug can be made, Zellner said.

The study was funded by the UCSF Foundation for Cardiac Research. Other researchers include: Amanda Browne, BS, Dorina Gheorghevici, MD, Alice Guh, BS, UCSF Vascular Lab; Krishnankutty Sudhir, MD, Baker Medical Institute, Melbourne, Australia; Kanu Chatterjee, MD, Tony Chou, MD, UCSF.