Growth hormone (GH) is a chemical produced by the body to regulate the growth of bones and muscles. During puberty, growth hormone determines how each person grows, especially height. For people whose bodies produce too little growth hormone (growth hormone deficiency) synthetic GH can be prescribed as an injection. For these people, adding GH can lead to increased bone density, increased muscle mass, decreased body fat, and increased ability to exercise.
GH and Athletes
Growth hormone is sometimes used (and abused) by athletes trying to gain a competitive edge. The use of GH, just like other hormones such as testosterone, is banned by the sporting community. In addition, the belief that GH can increase muscle mass and decrease fat are not supported by scientific evidence. There are limited studies available tracking GH use in otherwise healthy adults. In general, researchers have found that taking GH appears to bring about an increase in lean body mass, but in reality the gain is mostly due to water retention with no corresponding increase in muscle mass or strength. However, a new study reported in the Los Angeles Times in May, 2010 indicates that injections of GH may boost sprint speed for some athletes. Further studies will need to be done to verify this claim.
GH and Aging
Growth hormone is also sometimes promoted as a way to slow the aging process. As we age, the amount of growth hormone produced by the body naturally declines. There are no studies conclusively reporting that GH supplements can slow the aging process. In addition, a study published by the Endocrine Society shows that older men who have higher levels of certain growth hormones are at increased risk of dying from cancer.
Growth Hormone Facts
The only way to legally obtain GH is through a prescription for injections. Doctors are allowed to write prescriptions for GH only for patients whose blood work shows a deficiency of natural GH. Growth hormone taken orally (as a pill) is known to be ineffective because digestion eliminates the beneficial qualities of the drug.
Any benefits gained from GH are temporary. Once the drug is stopped, the benefits will gradually dissipate over several weeks. In addition, GH injections can cause unpleasant side effects including muscle pain, fluid retention, and swollen joints.
Overall, the legality, side effects, and cost of GH use are prohibitive. Studies show that working out is more effective than GH supplements at boosting muscle mass for athletes. Doctors recommend exercise and a healthful diet to promote good health at all ages.
Sources:
Hormone.org
Mayo Clinic
Los Angeles Times
Endocrine Society: Growth Hormone
Endocrine Society: Growth Hormone Cancer Risk
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