By Karlis Ullis, MD with Josh Shackman, MA
I was one of the first private practitioners in the country to dispense growth hormone as part of an overall anti-program hormone replacement program for adults that fit the criteria of the “Adult Onset Growth Hormone Deficiency Syndrome”. Like many other anti-aging physicians, I was extremely impressed by the initial research on growth hormone showing dramatic improvements in body composition, kidney function, skin, mood, well being, etc.
I have been a member of the Growth Hormone Research Society for many years and have closely followed all the latest research on growth hormone and other adult hormone replacement therapies. As the number of studies on growth hormone as well as testosterone has piled up since I first began prescribing testosterone, I believe now is the time to look back at the research and see if growth hormone and testosterone have lived up to their promises.
It is well established in bodybuilding circles that testosterone is superior to growth hormone for gaining muscle. However, growth hormone still is enormously popular and generally has a better reputation than testosterone both in bodybuilding and in anti-aging circles. The general impression is that testosterone will make you big, but at the price of acne, puffiness, temper tantrums, prostate enlargement, and possibly “gyno”.
Well it is acknowledged that growth hormone is not as anabolic as testosterone, people still think of growth hormone as a hormone that will make you lean and toned with almost no side effects. Growth hormone also has a reputation as being the “fountain of youth” among anti-aging enthusiasts, whereas testosterone is still considered somewhat dangerous. The purpose of this article is to see how the research on testosterone and growth hormone from the last few years has supported or disputed the public’s view of these two hormones.
Which is Better for Body Composition? – Growth Hormone or Testosterone
New research has shed some light on the anabolic effects of growth hormone. Several studies in the past have shown an increase in lean body mass in subjects taking growth hormone. However, lean body mass does not necessarily mean muscle, but anything that is not fat and this includes water, organ tissue growth, bone mass, and connective tissue growth. My friend Michael Mooney (author of Built to Survive and editor of the Medibolics Newsletter) has helped publicize the fact that not much, if any, of the lean mass gained while on growth hormone is actually muscle.
One recent study on HIV positive test subjects showed no significant change in skeletal muscle mass after taking six milligrams (about 18 units) per day of growth hormone for 12 weeks.(1) Another study, also on HIV positive test subjects, also showed a lack of muscle growth when doses of nine milligrams (roughly 27 units) per day were given.(2) Keep in mind that HIV positive individuals are often suffering from muscle wasting conditions, which should make them more responsive to any possible anabolic effects of growth hormone. Growth hormone is probably equally ineffective in healthy individuals.
One study on young (aged 22-33), highly trained athletes did show a significant increase in lean mass after six weeks of taking 2.67 milligrams (about 8 units) per day.(3) However this increase was only 4%, and may have not included any muscle mass at all. It seems overwhelming clear that growth hormone is either non-anabolic or very weakly anabolic for skeletal muscle when taken by itself, and it definitely not worth the large price if you are taking it solely for gaining muscle. The only real use in gaining muscle may be as a synergistic agent with testosterone.
A synergistic effect of taking growth hormone with testosterone has been reported for increases in lean mass, but further research needs to be done to see if this synergistic effects holds for skeletal muscle. Keep in mind that some increases in lean mass are not desirable. Growing some organs too big such as kidneys can produce some embarrassing effects seen in some professional bodybuilders. You do not want your “guts” sticking blatantly out of your body.
But enough on growth hormone for muscle gain. For information, see Bryan Haycock’s article in this issue or go to Michael Mooney’s web site. If you are going to spend the money on growth hormone to try to improve your body, your best bet is to use it as a fat loss or “sculpting” agent. The previously mentioned study with growth hormone on trained athletes did show an impressive 12% decrease in bodyfat. So well it is well established that testosterone is far, far better for building muscle than growth hormone, is growth hormone the better choice for fat loss? The research on this issue is mixed, and there is no easy answer to this question.