WASHINGTON, July 23 (Reuters) - U.S. teenagers' reported use of synthetic human growth hormone more than doubled between 2012 to 2013 as they sought to improve athletic performance and appearance, a survey by anti-drug advocates found.
Eleven percent of 3,705 teenagers in grades 9 to 12 polled by the non-profit Partnership for Drug-Free Kids said they had used synthetic human growth hormone at least once without a prescription, up from 5 percent in 2012.
Use of synthetic human growth hormone (HGH) was higher among blacks and Hispanics, at 15 percent and 13 percent, respectively. Caucasians were at 9 percent, according to the group's annual survey released on Tuesday.
Twelve percent of boys said they had used synthetic HGH compared with 9 percent of teenage girls.
"Young people are seeking out and using performance-enhancing substances like synthetic HGH - and supplements purporting to contain HGH - hoping to improve athletic performance or body appearance without really knowing what substances they are putting into their bodies," Steve Pasierb, head of the Partnership for Drug-Free Kids, said in a statement.
The findings underscored teenagers' growing interest in performance-enhancing substances and the need for better regulation and labeling of over-the-counter products implying they contain synthetic HGH, said the advocacy group, which aims to reduce youth substance abuse.
Synthetic HGH stimulates growth and cell production and helps regulate body composition, muscle and bone growth. It has limited prescription uses, including to combat muscle-wasting associated with the human immunodeficiency virus, and deficiency in adults due to tumors.
Taken illicitly, HGH can be used to improve athletic performance and appearance by building muscle, like anabolic steroids.
The survey said one in five teenagers said they had at least one friend who used steroids. The same percentage also said they thought it was easy to get steroids.
Eighty-one percent of teenagers in 2013 considered use of synthetic HGH without a valid prescription a "great" or "moderate" risk, down from 86 percent in 2012, according to the poll, which had a margin of error of 2.1 percentage points. (Reporting by Ian Simpson; Editing by Susan Heavey)