The authors of that study did not make any claims that the treatment had reversed the aging process and stressed that more research was needed to draw any conclusions. But they did note that the increase in muscle and decrease in fat were "equivalent in magnitude to the changes incurred during 10 to 20 years of aging."
The statement attracted a heap of media attention, which triggered an explosion in use of growth hormones for anti-aging purposes. The NEJM tried but failed to quiet the hype with an editorial accompanying the article-- and one in 2003-- that warned against using growth hormones as an anti-aging therapy.
"My suggestion is that growth hormone should not be used for anti-aging," Liu says. "Rather than looking at growth hormone as a magic bullet or [ticket to] the fountain of youth, if you want to increase your chances of living a long and productive life, you should do the things that your moms and doctors always told you: Eat right, exercise often, get enough sleep, and don't smoke."