Definition :
Dehydroepiandrosterone (DHEA) is a precursor (prohormone) of the sex hormones estrogen and testosterone. It is a steroid produced naturally by the adrenal glands and is also sold as a dietary supplement.
Purpose :
Many claims have been made for DHEA including that it fights aging, burns fat, increases muscle mass,
boosts the immune system, eliminated symptoms of menopause, prevents Alzheimer’s disease, and can treat everything from inflammatory bowel syndrome to cocaine withdrawal. There is little or highly questionable evidence to support most of these claims. DHEA does have medical uses in treating adrenal insufficiency (Addison’s disease) and systemic lupus erythematosus (SLE).
Description :
DHEA is a supplement with a long history of controversy. In the 1980s it was promoted by supplement makers as a ‘‘miracle’’ product that would improve athletic performance, build muscle, burn fat, restore sexual potency, and prevent aging. Many of these claims are still made by supplement makers today. In 1985, the Food and Drug Administration (FDA) banned DHEA for sale in the United States because of its potential for abuse and the high risk of serious side effects. DHEA was also banned by several sports organizations including the International Olympic Committee and the National Football League. However, in 1994, the United States Congress passed the Dietary Supplement Health and Education Act (DSHEA). Under this law, DHEA met the definition of a dietary supplement and could once again be sold without a prescription in the United States.
DSHEA regulates supplements such as DHEA in the same way that food is regulated. Like food manufacturers, manufacturers of dietary supplements do not have to prove that their product is either safe or effective before it can be sold to the public. Manufacturers of conventional pharmaceutical drugs, however, must prove both safety and effectiveness in humans before a new drug is approved for use. With dietary supplements, the burden of proof falls on the FDA to show that the supplement is either unsafe or ineffective before it can be restricted or banned. Information about a supplement’s safety and effectiveness is normally gathered only after people using the product develop health problems or complain that the product does not work. In the mid-2000s, there was pressure to reclassify DHEA as a hormone and ban its over-the-counter sale, but dietary supplement manufacturers have successfully fought this move. Federal law requires that all manufacturers of dietary supplements and over-the counter drugs report consumer complaints of adverse events (negative side effects) to the FDA. This makes accumulating information on the safety of DHEA faster and easier.
DHEA is produced mainly in the adrenal glands. These are small, compact hormone-producing tissues located just above each kidney. The adrenal glands convert cholesterol into DHEA and release it into the bloodstream. DHEA is also produced in smaller amounts by the testes, liver, and possibly the brain.
DHEA is a prohormone, meaning that the body can convert it into several different hormones including
the female hormone estrogen and the male hormone testosterone. During development, the fetal adrenal
glands produce large amounts of DHEA. After birth, production drops and remains low during childhood. As adulthood approaches, the rate of DHEA production increases, reaching a peak between ages 25–30. From age 30 on, the level of DHEA declines steadily until by age 80, men have only about 10% as much DHEA in their blood as they did at age 25.
Some researchers, observing the relationship between aging and decreased levels of DHEA, hypothesized the decrease in DHEA caused age-related problems such as cardiovascular disease, decreased sexual function, and dementia. They theorized that aging could be delayed using dietary supplements to restore DHEA levels to those of a younger person. This was only a hypothesis and had not been tested, yet supplement manufacturers grabbed on to the cause and effect idea and began promoting DHEA as a miracle supplement that could increase longevity and ward off a number of age-related changes.
The researchers tended to be much more cautious. For one thing, humans and other primates (apes, monkeys) produce substantial amounts of DHEA, but common laboratory animals such as rats and mice produce almost none. Therefore, it is unclear whether results of testing DHEA in lab animals can be applied to humans. Some researchers have spoken out against supplement makers, complaining that their research has been taken out of context, misrepresented, or just plain altered to support the claims of manufacturers selling DHEA, especially those selling over the Internet.
DHEA’s role in health care
DHEA has two uses accepted by practitioners of conventional medicine. Under supervision of a physician, DHEA has been used to successfully treat Addison’s disease. Addison’s disease is the result of adrenal insufficiency. The adrenal glands do not produce enough hormones. DHEA supplements simply replace what the body should be making.
DHEA has also been used by physicians to treat symptoms of systemic lupus erythematosus (SLE). SLE is a complicated autoimmune disease where the body attacks and damages its own tissues. It is not
clear why DHEA improves SLE symptoms such as joint pain and inflammation of the tissue surrounding the heart, but the majority of clinical trials in humans support this use.
There is mixed evidence to support two other claims for DHEA—that it helps with weight loss and that it relieves depression symptoms. A rigorous study led by researchers at the Mayo Clinic and published in 2006, found no anti-aging effects in elderly participants who took DHEA for two years. There were no measurable improvements in muscle strength, body fat, physical performance, insulin sensitivity, or quality of life.
DHEA is sold as a dietary supplement in the form of tablets, capsules, and a liquid injection. Dosages range from 25–250 mg per day. An independent study of DHEA supplements found that many supplements contained amounts DHEA ranging from 0–150% that were inconsistent with the amount described on the label.
Dietary supplement manufacturers continue to use unsubstantiated claims about DHEA that appeal to individuals searching for the fountain of youth. These include claims that DHEA improves memory, eliminates or improves symptoms of Alzheimer’s disease, prevents cardiovascular disease, increases bone density, treats chronic fatigue syndrome, treats cocaine withdrawal, improves symptoms of Crohn’s disease and inflammatory bowel syndrome, slows the development of AIDS, restores fertility, cures erectile dysfunction, treats symptoms of menopause such as hot flashes, helps manage schizophrenia, increases muscle strength and athletic performance, stimulates the immune system, prevents skin aging, and treats the symptoms of fibromyalgia. There are no independent, controlled, rigorous studies to support any of these uses. The National Center for Complementary and Alternative Medicine (NCCAM) does not recommend the use of DHEA supplements as a means to improve any health problems. The National Institute for Aging (NIA) advises against the use of DHEA supplements due to the lack of evidence proving any form of anti-aging benefit.
DHEA remains of great interest to researchers. Clinical trials are underway to determine safety and effectiveness of DHEA in a variety of situations.
Precautions :
People under age 40 should not take DHEA supplements.
Pregnant women should not take DHEA. There is some evidence that it can induce early labor. The effect on the developing fetus is unknown.
Breastfeeding women should avoid DHEA supplementation because DHEA passes into breast milk and may affect development of the infant.
People who have a high risk of developing estrogen- or testosterone-sensitive cancers, such as breast cancer or prostate cancer, should not take DHEA supplements. DHEA is converted into estrogen or testosterone. These hormones appear to stimulate the growth of certain cancers.
Athletes should be aware that some athletic governing bodies ban DHEA supplement use and test for abnormally high levels of DHEA as part of routine drug testing.
Interactions :
High levels of DHEA may interfere with the way the liver processes certain drugs. As a result, these drugs may accumulate in the body in high levels and cause adverse effects or be more rapidly deactivated and not produce a therapeutic response. Drugs that may be affected by high levels of DHEA are anticonvulsants, antipsychotics, corticosteroids, oral contraceptives, hormone replacement therapy drugs, insulin, and drugs to treat insomnia.
Complications :
DHEA supplementation in healthy people can cause major side effects. Many of these come about because of the conversion of DHEA into high levels of testosterone and estrogen. These include:
- masculization of women, including deepening voice and increased body hair
- menstrual irregularities in women
- feminization of men including, enlarged breasts and shrunken testicles
- decreased HDL (‘‘good’’) cholesterol
- high blood pressure (hypertension)
- liver damage
Less serious side effects include acne, increased sweating, breast tenderness, insomnia, nausea, and abdominal pain.
Parental concerns :
DHEA should never be given to children. Parents should keep this and all drugs and supplements stored safely out of reach of children to prevent accidental poisoning.
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