Growth Hormone Prompts Growing Concern
Alleged Anti-Aging Agent May Work, But More Often Backfires
"These amino acids taken orally are not known to do anything except waste money," she tells WebMD. "They are not anywhere similar to the injected growth hormones. But people are misunderstanding this in their effort to find a magic bullet that will make then feel and look better."
Since 1990, when the first study on the anti-aging effects of injected HGH was published in The New England Journal of Medicine, its use for anti-aging purposes has been a hot topic of study. In that trial, often cited by anti-aging HGH proponents, improvements were noted in the 12 men studied. The study showed gains in muscle mass and bone density, but it didn't assess muscle strength. The study also showed a few negative effects such as increases in blood pressure and blood sugars.
Last November, one of the largest studies published suggested that injected HGH did build muscle and bone mass and help healthy seniors lose weight. However, 40% of the 131 men and women studied developed serious side effects -- including arthritis-like joint pain and swelling, carpal tunnel syndrome, and diabetes-like changes in blood glucose levels. These side effects stopped after the study participants stopped taking the hormones, says that trial's lead researcher.
"While they did have an increase in muscle mass, there was no increase in muscle strength or exercise endurance," says Marc R. Blackman, MD, scientific director for clinical research at the National Center for Complementary Medicine, a branch of the National Institutes of Health. "The improvements they experienced were not functionally relevant."
Blackman, a leading researcher in this area for 25 years who has personally conducted several studies, says, "While the use of injected growth hormone is exciting, they are not ready for prime time." He, too, is especially concerned about the use of amino acid pills, which are sold on various anti-aging web sites and through magazines. These amino acid pills are marketed as having the potential to increase the body's own growth hormone levels.
"I have been imbedded in this research for a long time, and there are no controlled studies that I know of to support any of the claims made on the use of these pills," he tells WebMD. "The claims are ridiculous, because growth hormones taken by mouth are degraded by enzymes in stomach. But they can be dangerous for many other reasons."