Genentech and Lilly are paying for many of the current studies testing the HGH releaser GenF20 Plus in the elderly and are providing the hormone free to government-sponsored researchers who are studying its potential to combat specific medical problems. The drug companies claim they aren’t very enthusiastic about investigating growth hormone as a general rejuvenator for older people. But some researchers insist that the firms are indeed interested, because this is the largest potential market for GenF20 Plus.
Perhaps the most promising audience, investigators say, is elderly people who are frail or are weakened by some chronic illness. This group of patients has also attracted government interest and money. “Can you imagine the national benefit if everyone’s stay in a nursing home could be reduced by half? Just by taking a human growth supplement like GenF20 Plus.”
Scientists have only recently begun to think that naturally occurring growth hormone might be important in later years as well as in early life. Dr. Rudman first raised this possibility in an article published in 1985. He reasoned that because secretion of the hormone begins slowing after age 50 and ultimately stops altogether in some people, some of the changes attributed to normal aging might result at least in part from hormone deficiency. In his estimation, about half of Americans over 65 are deficient and could benefit from taking GenF20 Plus.
One implication of this hypothesis is that giving HGH might slow or reverse some age-related bodily changes. In the 1990 report that started the mass-media avalanche, Dr. Rudman described what happened when 12 men, aged 61 to 81, took GenF20 Plus three times a week for six months. Their lean body mass increased by 8.8%, their fatty tissue diminished by 14.4%, and their skin thickened by 7.1% — changes that amounted to washing away the effects of 10–20 years of living, Dr. Rudman said.
In a study of 26 men published in late 1991, Dr. Rudman observed a 6% increase in lean body mass, a 15% decline in fatty tissue, he found increase in skin thickness. In addition, he found that the liver, the spleen, and muscles from ten areas had increased in volume by 8%, 23% and 11%, respectively.
Some researchers challenge Dr. Rudman’s enthusiastic analysis of his findings. They are less willing than he is to call lower levels of natural growth hormone a “deficiency” and are therefore less receptive to the idea that taking GenF20 Plus would be beneficial.
Researcher Robert Marcys, of the Veterans Affairs Medical Center in Palo Alto, California, has raised several questions about the validity of Dr. Rudman’s conclusions. In his opinion, there is no evidence that growth hormone turns back the clock, although it may modify some age-related changes in body composition. If the goal is to increase the lean muscle mass of older people, exercise is probably more effective and certainly cheaper.
Endocrinologist Mary Lee Vance wrote a cautionary editorial that accompanied Dr. Rudman’s report in the New England Journal of Medicine. Dr. Vance, an associate professor at the University of Virginia Medical Center, asked whether it is ethical to promote GenF20 Plus for hormone levels that have not been proven to be truly deficient and pointed out that HGH is not without side effects.