DHEA: The truth about anabolic acid.
By Ellen Coleman, RD, MA, MPH
Build muscle! Burn body
fat! Slow the aging process! Such are the claims for
one of the hottest-selling nutritional supplements -- DHEA.
DHEA (dehydroepiandosterone) is an adrenal
hormone that functions as a metabolic precursor for the production of
testosterone, estrogen, and other hormones. The highest levels of circulating
DHEA are reached between the age of 20 and 30. By age 80, DHEA levels
are only 10-20% of those produced at age 25. Because DHEA and testosterone
levels decline with age, DHEA proponents claim that supplementation
will increase testosterone levels, thereby producing both anabolic and
anti-aging effects.
Although DHEA is banned by the International
Olympic Committee and the National Collegiate Athletic Association,
some athletes are experimenting with it as an alternative to anabolic
steroids. However, athletes who are using DHEA to bulk up
may be in for a disappointment. There is no evidence that DHEA produces
anabolic effects (e.g. increased muscle mass or strength), or decreased
body fat in healthy, young adults (1).
The side-effects of DHEA supplementation
can include oily skin, acne, extra growth of body hair, liver enlargement,
and aggressiveness. Indiscriminate use of DHEA by young adult athletes
is of particular concern, since the hormone’s long-term safety has not
been established. As with other hormones, adverse effects due to DHEA
administration may not appear for years. Individuals who have a family
history of breast or prostatic cancer should not take DHEA (2).
DHEA has been labeled the steroid
of youth. Several studies have found a positive correlation between
increased serum DHEA levels and improved vigor and well-being. DHEA
supplementation increases the androstendiol levels of older men, but
not their testosterone or dihydrotestosterone levels. By comparison,
DHEA supplementation increases all three levels in older women (2).
In a study of older adults, 50 mg of supplemental
oral DHEA per day increased serum DHEA levels to those found in young
adults (3). Serum concentrations of insulin-like growth factor increased
by 10%. DHEA supplementation also elicited positive feelings (improved
sleep, greater energy, and increased ability of handle stress) in 82%
of women and 67% of men. No changes in libido were noted.
Although DHEA supplementation has raised
concerns in the medical community, the hormone is readily available.
Unlike hormones such as testosterone and estrogen, DHEA is sold over
the counter and by mail order as a nutritional supplement. DHEA belongs
to a group of hormones that were freed for over the counter sales by
the 1994 Dietary Supplements Health and Education Act (DSHEA).
The DSHEA also prohibits the Food and Drug
Administration from taking DHEA off the market unless the agency can
prove that using the hormone will create a medical problem. Unfortunately,
this law places the burden of proof of DHEA’s safety on the over-taxed
FDA rather than on the companies profiting from the sale of the hormone.
Athletes should completely disregard claims
that Mexican yam (Dioscoria) supplements provide the building
blocks for DHEA. Mexican yam supposedly contains a DHEA processor
which the body can convert to DHEA. While Dioscoria does contain a plant
sterol ring called diosgenin, which is a processor for the semisynthetic
production of DHEA and other steroid hormones, this conversion only
takes place in the laboratory. The claim that Mexican yam supplements
increase the body’s production of DHEA (or testosterone) is a complete
scam (2).
In the mid-1980’s, several DHEA products
sold in health food stores were found to contain little or no DHEA.
In 1985, the FDA ordered manufacturers to stop marketing DHEA products
as weight-loss aids.
The preceding article was reprinted with permission
from the author.
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