Anti-Aging Supplement May Clog Arteries
But tests on DHEA were only done in the lab
THURSDAY, Dec. 4, 2003 (HealthDayNews) -- Adding another chapter to the conflicting history of medical reports about the supposed "anti-aging" supplement DHEA, a new study suggests the hormone could contribute to clogged arteries.
Researchers examined the effects of DHEA only in laboratory tests, not in humans. Even so, the study's authors are recommending against use of the supplement outside of research.
"People should refrain from taking DHEA in an unsupervised fashion," says co-author Dr. Martin K.C. Ng, a cardiologist at Royal Prince Alfred Hospital in Sydney, Australia.
DHEA, which the body produces naturally, has become one of the most popular and controversial dietary supplements on the market. Among other things, proponents say DHEA can boost the immune system, improve memory, help people lose weight and combat low sex drives. The last benefit may be the biggest grabber.
"Aging gentlemen often take DHEA to supplement their diet, hoping that will boost their testosterone," says Dr. Michael V. Sofroniew, a professor of neurobiology at the University of California at Los Angeles.
Indeed, DHEA is directly linked to testosterone and other hormones. DHEA was originally thought to serve mainly as a kind of parent to the other hormones, but now researchers think it serves purposes of its own, Sofroniew says.
For the most part, however, DHEA remains "pretty mysterious," Sofroniew says. Body levels of DHEA peak during adolescence and then drop off, with especially low levels reported among depressed people. But it's not clear if those levels are a cause or effect of depression, Sofroniew adds.
Some researchers have suggested DHEA may prevent heart disease, but no one has examined that theory by launching a sophisticated test among humans, Ng notes. "In fact, very little is known about the potential effects of DHEA on heart disease," he says. "Despite this lack of evidence for safety or benefit, many people are taking DHEA in the U.S. on an unsupervised, over-the-counter basis."
Ng and his colleagues exposed human cells to DHEA and watched the results. They report their findings in the Dec. 3 issue of the Journal of the American College of Cardiology.
The study found DHEA may actually promote heart disease. When under the influence of DHEA, some cells appear to take in more cholesterol, potentially clogging arteries.
However, "a limitation of our study is that we studied the direct administration of DHEA to human cells on a plastic dish rather than to a human being," Ng admits. In humans, the interaction of hormones is more complicated, he explains.
At this early point in research, it's not clear if the potential risks to the heart posed by DHEA may be as dire as those posed by smoking, diabetes and obesity, Ng says. But he still advises plenty of caution about its use.
Peter J. Hornsby, a professor of physiology at the University of Texas Health Science Center, agrees that DHEA's effects on the heart remain unclear, especially considering that young people naturally have high levels of the hormone but don't seem to suffer from ill effects.
For the time being, it's "very dangerous" for people to take DHEA on their own, Hornsby says. "We don't know what the normal function of this hormone is in young adults, and we have no idea why we have this hormone" in the first place.
To learn more about DHEA, try quackwatch.org for a skeptical view. The Council for Responsible Nutrition, a supplement trade group, says it can't recommend whether its members should sell DHEA. Also, the Mayo Clinic has a page on anti-aging therapies.