Growth hormone's risks outweigh its benefits.

Human growth hormone has substantial risks and no functional benefits for healthy, elderly people, according to a comprehensive review.

Injections of the substance are an approved therapy in children and adults who have growth-hormone deficiency, a defect that can lead to short stature and other health problems. It's a valuable medicine for those individuals, says Hau Liu of Stanford University.

But an estimated 30,000 generally healthy people in the United States, mostly elderly adults, take the hormone for its putative antiaging effects. Various organizations that promote growth hormone for this purpose often cite a 1990 research finding that growth hormone promotes fat loss, muscle-mass increase, and maintenance of healthy skin.

"Based on the evidence we reviewed, which includes the evidence [from 1990], we do not recommend growth hormone for antiaging," Liu says.

He and his colleagues reviewed studies based on 19 separate trials that analyzed the hormone's effects on healthy adults. The 1990 study was the least rigorous, Liu says.

In the clinical trials, volunteers who took growth hormone experienced significantly more swelling in joints and extremities, more carpal tunnel syndrome, and more joint pain than did participants who received a placebo.

On the other hand, hormone-treated volunteers lost 1.7 more kilograms of fat and gained 1.5 more kg of lean body mass, on average, compared with their peers. However, the researchers found no evidence that those changes reduced disability or disease.--B.H.