Growth hormone doesn't slow ageing

Growth hormone is not a useful therapy for 'setting back the clock' in elderly individuals. The beneficial changes in body composition that the hormone produces are small and side effects are common. Growth hormone is widely used as an anti-ageing treatment, even though the US Food and Drug Administration has not approved it for this purpose. Secreted by the pituitary gland, growth hormone promotes growth during childhood and adolescence. It acts on the liver and other tissues to stimulate insulin-like growth factor, which leads to its effects. However, blood levels of circulating insulin-like growth factor tend to decrease as people age or become obese. Several studies have shown that growth hormone treatment can improve body composition, bone density, cholesterol levels, and may even stave off death in growth-hormone deficient individuals. The safety and effectiveness in healthy individuals seeking an anti-ageing solution, however, is unclear. Researchers from the Stanford University in California, USA, examined the risks and benefits of hormone therapy in elderly individuals by analysing data from relevant studies. Data from 31 studies with a total of 220 participants were included in the analysis. The average patient age at the start of the study was 69 years and the most of the subjects were overweight but not obese. The average initial growth hormone dose was 14 micrograms per kilogram per day, and the average treatment duration was 27 weeks. Although statistically significant, the drop in overall fat mass and the increase in lean body mass were small, -2 kg and 2kg, respectively. The net effect of these changes was that body weight did not change significantly. Growth hormone therapy led to a decrease in total cholesterol levels, but the reduction was not statistically significant after accounting for body composition changes. Growth hormone had no apparent effect on bone density or fat levels in the blood plasma. As noted, the side effects were common with growth hormone therapy and included swelling, joint pain, gynaecomastia, (breast development in men), and carpal tunnel syndrome (painful compression of the median nerve that extends from the forearm into the wrist.) In addition, growth hormone therapy may have slightly increased the risk of diabetes. Although growth hormone has been widely publicised as an anti-ageing therapy and initial studies suggest that it might be clinically beneficial and safe in the healthy elderly, the above study found little evidence to support these claims. On the basis of available evidence, growth hormone cannot be recommended to reverse age related changes.