Jack Benny, the late comedian who perpetually gave his age as 39 once said that growing old is a case of mind over matter. "If you don't mind, it doesn't matter."

The problem is that most of us do mind. This is especially true of the millions of graying baby boomers, creating a vast opportunity for a new wave of doctors pharmacists and marketers who claim they can slow the process down.

The first hint that such a process could be achievable came in a study that was published in the July 5, 1990 New England Journal of Medicine by Dr. Daniel Rudman. He tested the notion that older people lose muscle and gain fat because they produce less growth hormone. In that study 12 men between ages 61 and 81 were given small doses of growth hormone and after six months they showed a 9 percent increase in lean muscle mass and a 14 percent decline in fat with a noticeable increase in bone density.

"The overall deterioration of the body that comes with ageing in not inevitable," Rudman wrote. "We now realize that some of the aspects of it can be prevented or reversed." Rudman came to regret his choice of words in that many observers overlooked the inherent flaw of this study, namely the small test group and short-term follow up. It did not matter that an accompanying editorial warned that some of the subjects experienced side effects and that the long term effects of HGH were unknown.

From that national attention a growth hormone and anabolic steroid gold rush ensued. Within two years the American Academy of Anti-Ageing Medicine was established. It states it has 12,000 members. The internet has added another dimension to the HGH marketplace. Thousands of Web sites and spam e-mailers are promoting alleged HGH releasers, oral and homeopathic hormone products.

The FDA originally approved HGH for treatment of stunted growth in children and then for atrophy in AIDS patients. By later authorizing it for "adult growth-hormone deficiency" many unprincipled doctors interpreted this syndrome loosely in order to prescribe for non-medical reasons.

Even adult growth-hormone deficiency syndrome is hard to describe as there are no universally accepted standards for each age group. It is difficult to distinguish between normal age decline and hormonal deficiency.

Some anti-ageing proponents make promises about prolonging longevity while others claim to extend the length of the "health span" rather than the life span. The foremost leader in the field of age management medicine is Cenegenics, a privately held company with about 10,000 patients and annual revenues of $50 million.

Their philosophy is that of aggressive prevention through metabolism modulation. At a annual cost of about $10,000 per year each patient care is individualized by a battery of tests that help formulate a treatment course.

This may include recommendations for a low glycemic diet, exercise regiment, multiple vitamins and nutritional supplements and if there is evidence of low testosterone levels treatment, which normally happens after age 30, then with injections of human chorionic gonadotropin which stimulates the testes to secrete more testosterone. Incidentally this alternative use of HCG is legal.

The role of testosterone in ageing is not clearly defined. It is known that low testosterone contributes to a loss of lean muscle mass, bone density, energy and libido. A small minority of physicians believe in the idea of "male menopause," specifically when the testicles stop responding to stimulants such as HCG, essentially shutting down. The endocrine society does not hold that idea and does not recommend offering testosterone to all older men with low testosterone levels. "This intervention is yet to be proven at best and dangerous at worse." On a broader scale it is clear that hormone replacement can increase the risk for cancer, cardiovascular disease and behavior changes.

It is interesting how the same body of scientific data can produce strong and opposing points of view. What is agreed upon by most is that there is a paucity of well formulated placebo-controlled, long-term studies with long term duration. It is easy to be lured by anecdotal evidence which is the main mode of marketing for most anti-ageing centers.

Testimonials may sell products or ideas but they should not be considered scientific evidence by any stretch of the imagination. Unfortunately the promoting of anti-ageing remedies by physicians may falsely provide treatment credibility to the unsuspecting lay person.

The question has to be asked what constitutes responsible cutting-edge science as opposed to reckless pushing of the envelope. What distinguishes a vanity fix from quality of life improvement? Is vitality and energy at an older age a good trade off for the risk of a potentially shorter life span?