No One Really Knows If HGH Is Bad for You

In an earlier report on human growth hormone (HGH), known simply as growth hormone in scientific circles, I took athletes like Roger Clemens to task for lying about taking it to increase their field performance. It's an obsolete tactic to employ, especially during a period in which superstars like Sylvester Stallone not only take it to bulk up for films like his latest Rambo roid rage-fest, but also advise anyone within range that they should hop on its juice as well. Sure, Clemens was on the line for perjury, dragged as he was in front of Congress on the matter, but, as hoops stars say all the time, the ball don't lie. And Clemens's stats in his declining years in baseball don't tell the story of an aging great whose body can't hold up against the strain: They tell the tale of someone who, against entropy and all common sense, managed to stave off the aging process long enough to pick up a couple World Series wins, Cy Young awards and hundreds of millions.

But that would only be part of the tale. The rest of it isn't as exciting as the Mitchell Report, or watching baseball titans like Clemens and Mark McGwire humbly schlep to Washington for some long-deserved scrutiny on their garish records and paydays. That's because the rest of the tale is about the science, rather than the hype, of HGH.

And like the ball before it, the science don't lie.

Let's get unequivocal: HGH is highly capable of increasing lean muscle mass, overall metabolism, calcium retention, skin elasticity, bone mineralization, protein synthesis and even homeostasis, which is to say, some of the most important aspects of physical development. It can also significantly decrease fat mass, which, these days, is almost as important a psychological development as a physical one. Bodybuilders are entranced by its ability to turn them into behemoths, and pro athletes love the way it has proven to help them recover from their injuries. But it doesn't stop there: According to acolytes, it can even increase the sex drive, offer better REM sleep and stimulate the immune system. Its benefits, such as they, are nevertheless socially legitimized by its meteoric rise, as around 300,000 weekend warriors, pro athletes and Average Janes and Joes spend an estimated $2 billion on it annually, in the process increasing the stock of companies like Pfizer, Genentech, Merck, Lilly and onward, who sell synthetic versions of the naturally occurring hormone over the counter.

But, as a Stanford University study released in March 2008 explained, that doesn't mean that taking HGH will in any way make you an athlete as capable as Clemens, or even Stallone. Which makes sense: Just because you're huge doesn't mean you can actually hit a 90 mph fastball or tackle Tom Brady. As scientists continually take pains to remind us, everything depends on the details, and those vary by person. What the science does know, however, is that extended use can have adverse effects, from diabetes and joint inflammation to high blood pressure, heart failure and perhaps cancer.

"What we found suggested that it didn't help, and at some point, it might hurt," the study's lead investigator Hau Liu told the San Jose Mercury News shortly after it was published in Monday's issue of the Annals of Internal Medicine. "In addition," Liu explained in the study's conclusion, "growth hormone in the healthy young is frequently associated with adverse events."

But even Liu admits there are too many caveats in the Stanford study for it to be a convincing case, something that seems to occur with regularity when it comes to the scientific community and growth hormone. For one, the study analyzed smaller doses than those taken by professional athletes, and it considered only HGH alone, rather than its efficacy in muscle cocktails making the rounds of stadiums, locker rooms and gyms near you. Those cocktails include everything from insulin to anabolic steroids to other hormones and beyond, which, when mixed together, can achieve a cumulative result unattainable by reliance upon one substance.