Human Growth Hormone

Claims, Benefits: Will slow or reverse the aging process, boost muscle strength, renew energy, and keep you healthy.

Bottom Line: There's no evidence for this. And there's no way of knowing what's in the supplements on the market or what they'll do in your body.

Full article, Wellness Letter, June 2003:

Growth Industry: Seeking the Fountain of Youth

Growing old is not always a welcome change. Reduced fares on public transportation and senior movie tickets are not enough to make up for the declines in strength, youthful appearance, health, sexual desire, and self-confidence that can accompany aging. And thus it is predictable that people will look for methods to slow the process or turn it around entirely. One such “method” that’s gaining popularity is human growth hormone (GH).

Hormones are powerful regulators and orchestrators of our bodies and behavior. Levels of various hormones vary throughout our life spans. GH, also known as somatotropin, is one example. This very important hormone, produced by the pituitary gland in the brain, controls growth and development from infancy through adolescence and begins to decline around age 20. Some children with pituitary disease may have a deficiency of GH, and thus fail to develop properly. They may show changes that resemble aging, including loss of muscle. Prescription doses of injectable GH are approved for use—and are very useful—for such children. But it’s normal for older people to have lower levels of GH, and injecting them with this hormone in the hope of keeping them young is another matter entirely.

In recent years scientists interested in the processes of aging have begun to study GH, and in 1990 a small study of older men, published in the New England Journal of Medicine, showed that high doses of injected GH could reduce body fat and increase muscle mass somewhat. The treatment seemed to improve skin thickness slightly and to increase bone density. This report gave rise to a whole industry. Anti-aging clinics sprang up all over, offering injections of GH, as well as other hormones.

No one knows how many Americans avail themselves of GH treatments—100,000 according to one estimate. And no wonder many people try it, given the heavy promotion on the Internet and elsewhere, along with the newspaper headlines (“Growth Hormone Therapy for Elderly Promising”) designed to snag your interest and raise your hopes.

But what does it all mean?

Other studies in the past decade have had similar findings—that GH injections in the elderly can reduce body fat and increase lean tissue. But this is essentially meaningless—no one has been able to demonstrate that these changes in body composition have any beneficial effect on muscle strength, cardiovascular endurance, or quality of life. To get any increase in strength and endurance, you need to exercise while taking the hormone. But you can get the same benefits by just exercising. GH won’t add anything.

Not only is exercise better than GH, it’s a lot cheaper and safer. Among other troubling findings, GH may raise the risk of cancer, particularly prostate and breast cancer, and cause breast enlargement in men. It increases the risk of diabetes. Short-term side effects include fluid retention, which can promote carpal tunnel syndrome (a painful disorder of the wrist and hand) and joint pain. There’s the question of dosages, too. Nobody knows what the right dose might be.

On top of these drawbacks, GH is very expensive. Prices start at around $500 a month for the injections and go up to $2,000 a month for complete “anti-aging” regimens with other hormones, such as estrogen or testosterone. Those with pituitary disease really need GH, and this legitimate use is likely to be covered by health insurance. But GH as a possible weapon in the anti-aging arsenal is not covered.

“Releasers” and “precursors”

Plenty of “alternative,” nonprescription GH preparations—to be swallowed or inhaled—are available now. A few claim to contain real GH, but most claim to stimulate GH production in your body or to contain precursors that are supposedly converted into the hormone. If they did contain GH, it would not survive the trip through the digestive tract; and if you inhaled it, it would not be absorbed. As for the releasers, stimulators, and precursors, there’s no evidence that these work. But this doesn’t stop ads from referring to the 1990 study in the New England Journal of Medicine and all but claiming that the Journal endorses these products. Apart from the dishonesty of these ads, no one knows if these products are even safe. In 2003 an editorial in the Journal strongly disassociated itself from GH and subsidiary products as a “remedy” for aging and stated that the public is being misled.

Keep in mind: Experiments with hormones, including injected GH, as a means of building bone mass, improving skin, enhancing sexual performance, and otherwise restoring youth, have so far had discouraging results. The prescription form of GH is expensive and possibly dangerous. It might have some effects on body composition, but it won’t reverse aging.

Healthy aging is a commendable goal—we should all aim for it. But the fountain of youth does not exist, as Ponce de Leon might well have concluded after wandering around for years in what later became Florida. “Anti-aging” and “longevity” clinics can’t do anything except deplete your bank account. A healthy diet, regular exercise, a positive outlook, a regimen of preventive tests, good medical care, and a will to enjoy life—all these are far more likely to keep you youthful than any pills or injections yet known.

UC Berkeley Wellness Letter, June 2003
Updated May 2005