Q: Can taking human growth hormone slow down the aging process?
A: The answer so far is no. Human growth hormone injections have not been shown to be an effective anti-aging product.
The pituitary gland in the brain makes and secretes natural growth hormone. In combination with other hormones, such as IGF-1 (insulin growth factor 1), it is responsible for body development early in life.
Throughout your life, growth hormone continues to play a role in protein production and helps the body use fat for energy. Children deficient in growth hormone do not grow to their full potential height and have short stature. The FDA approved a synthetic human growth hormone (HGH) as a replacement in these children, which helps them grow taller.
As we age, the amount of growth hormone secreted by our pituitary gland naturally declines. By age 55, blood levels of growth hormone are about one-third lower than they are in people ages 18 to 35. This drop also coincides with the reduced muscle mass and increased body fat that happens with aging.
While healthy adults who take HGH might increase muscle by about 6% and reduce body fat by about the same amount, the risks greatly outweigh these possible small benefits.
There are downsides to using HGH. It can cause insulin to be less effective, which can raise blood sugar levels and increase the risk of diabetes. HGH also can lead to joint and muscle pain, breast enlargement, fluid retention, high blood pressure, and carpal tunnel syndrome.
And then there is this: Animal studies suggest that lower levels of growth hormone activity may lead to longer life. So, theoretically, HGH injections might actually shorten life span, challenging the notion that HGH is anti-aging.
The FDA has approved HGH in adults only for documented growth hormone deficiency. Synthetic human growth hormone is a prescription drug and cannot be obtained legally without a doctor's approval. To have any effect, it must be injected. Don't waste your money on pills containing HGH. The active ingredient is not absorbed when taken by mouth.
You can slow the tick of the clock with the time-tested formula of eating a healthy diet with enough protein and pursuing a regular program of aerobic and resistance exercise. This approach is better than any drug for enhancing your vigor and enjoyment of life.
(Howard LeWine, M.D., is an internist at Brigham and Women’s Hospital in Boston and assistant professor at Harvard Medical School. For additional consumer health information, please visit www.health.harvard.edu.)