Anti-aging hype

People have been searching for the fountain of youth for ages. And the lure of the advertising for anti-aging products can be hard to resist. Who wouldn't want to look and feel years younger simply by taking a pill?

But researchers have learned that aging is an intricate, complex process that involves many areas of the body. It's not likely that one product, pill or potion could be a cure for all the ills age can bring.

Researchers have found certain strategies that do work. Numerous studies show that exercise, a healthful diet and regular mental activity can help you live longer and better.

In addition, for women, estrogen replacement therapy has been found to help keep bones strong, reduce risk of cardiovascular disease, restore vaginal lubrication and improve skin elasticity. Evidence also suggests that it may help maintain mental function during aging.

But what about all the anti-aging remedies advertised today? Here's an overview of some of the most popular products:

Antioxidants

Antioxidants are vitamins, minerals and enzymes that protect the body by neutralizing "free radicals." Free radicals are byproducts of your cells' normal metabolism. They're believed to be associated with age-related changes and certain diseases.

Antioxidant supplements touted to fight diseases of aging include:

• Vitamin E — Of all the antioxidants, vitamin E shows the most promise for protecting against cardiovascular disease. It may also protect against Alzheimer's and Parkinson's diseases. If you have cardiovascular disease, the benefits of taking vitamin E — no more than 400 international units a day — probably outweigh any potential risks.
• Vitamin A and beta carotene — Several well-designed studies have found that supplements of beta carotene (which is converted into vitamin A in your body) offer no protection against heart disease. And two studies found an increased risk of lung cancer among smokers who took beta carotene supplements.

If you're interested in increasing your intake of vitamin A or beta carotene, you're probably better off eating more red and yellow vegetables than taking supplements.

• Vitamin C — Studies have shown that people who eat diets high in vitamin C (found mainly in citrus fruits) have lower rates of cancer and heart disease. However, it's unclear whether taking vitamin C supplements has similar benefits.
• Selenium — This antioxidant mineral is found primarily in seafood and liver. It may help prevent cancer. However, excessive amounts may cause hair and nail loss. More research is needed.
• Coenzyme Q10 — This antioxidant is produced by the body. It also has many dietary sources, including meat and seafoods. Claims that it can slow aging and stop the spread of cancer are unproven. However, some evidence suggests that it may hold promise as a treatment for congestive heart failure.

Although studies of some antioxidants are promising, caution is needed. It's not clear yet if taking antioxidant supplements is safe long term. For now, eating more antioxidant-rich foods, such as fresh fruits and vegetables, is better.

Hormones

Hormones are chemicals made by your body to regulate the activities of vital organs. Because hormone levels decline with age, some scientists speculate that hormones may play a role in the aging process. According to proponents of hormone products, you can set back the body's clock by restoring hormone levels to those of youth. Supplements include:

• DHEA — Dehydroepiandrosterone (de-hi-dro-ep-e-an-DROS-tur-own), or DHEA, is converted by the body into the sex hormones estrogen and testosterone. DHEA is most abundant in your body around age 25. After that, production wanes.

DHEA is sold over-the-counter. Proponents say it slows aging, increases muscle and bone strength, burns fat, improves cognition, bolsters immunity and protects against many chronic diseases.
However, there's no proof that DHEA supplements do any of these. While mice treated with DHEA do tend to act "younger," that doesn't mean the same happens in humans.

More troubling, DHEA may have harmful side effects. Even when taken briefly it may cause liver damage. It also may cause certain cancers, unwanted facial hair and an increased risk of heart disease.
DHEA was actually banned in 1985 by the Food and Drug Administration before it reappeared as an unregulated "dietary supplement."

• Testosterone — Declining levels of this male sex hormone have been linked with common complaints of aging — decreased energy and sex drive.

Anti-aging enthusiasts say increasing levels of testosterone (available by prescription) will improve energy, well-being, complexion and sex drive. Such claims remain unproven. In high doses testosterone can result in prostate problems, elevated cholesterol and fertility problems.

• Melatonin — This hormone is produced in the brain. It helps regulate sleep and holds promise as a remedy for insomnia and jet lag. But claims that melatonin (also a type of antioxidant) can slow or reverse aging, fight cancer and enhance sexuality are far from proven.

Supplements sold in stores typically contain many times the melatonin produced by your body. If taken improperly, melatonin can actually disrupt the sleep cycle.

• Human growth hormone (hGH) — This hormone, responsible for growth spurts in children, tapers off after adolescence. Proponents say injections of hGH (available by prescription) burn fat, build muscle and renew energy.

Some studies do suggest some benefit from hGH. However, these studies have been very small and most physicians say it's too early to draw solid conclusions from them. Possible side effects include fluid retention, joint pain, diabetes and high blood pressure.

No short cut

Despite tempting claims, there's no product proven to prevent or reverse aging. In addition, many have potentially dangerous side effects.
If you're considering using an anti-aging product, or you're concerned that you may have a hormone deficiency, talk to your doctor. He or she can help you decide whether the potential benefits of a product outweigh any risks