It’s no mystery that obese teenage boys are at a heightened risk of developing diabetes and heart disease, but a new study published last week in the journal Clinical Endocrinology found that obese boys have alarmingly low testosterone levels as well – between 40 to 50 percent less than males of the same age with a normal body mass index (BMI).
The study, conducted by researchers at the University of Buffalo, builds on earlier research the same scientists completed in 2004, which discovered low testosterone levels (hypogonadism) in older obese males ages 18 to 35, both diabetic and non-diabetic.
Dr. Paresh Dandona, lead author of the study, told the University of Buffalo News Center that he and his fellow researchers were “surprised to observe a 50 percent reduction in testosterone in this pediatric study because these obese males were young and were not diabetic.”
“The implications of our findings are, frankly, horrendous because these boys are potentially impotent and infertile,” Dr. Dandona, a Distinguished State University of New York Medical Professor and chief of the University of Buffalo’s Division of Endocrinology, added. “The message is a grim one with massive epidemiological implications.”
The study compared 25 obese with 25 normal-weight males, ages 14 to 20, controlling for age and sexual maturity and measuring concentrations of total and free testosterone (testosterone that isn’t chemically bound and thus available to the body). Levels of estradiol, a form of estrogen, were also measured.
“These findings demonstrate that the effect of obesity is powerful, even in the young, and that lifestyle and nutritional intake starting in childhood have major repercussions throughout all stages of life,” Dr. Dandona told UB News.
“The good news is that we know that testosterone levels do return to normal in obese adult males who undergo gastric bypass surgery,” Dr. Dandona said. “It’s possible that levels also will return to normal through weight loss as a result of lifestyle change, although this needs to be confirmed by larger studies.”
Testosterone (or lack of it) has been in the news a lot lately, thanks to a rash of aggressive advertising campaigns by the makers of prescription testosterone-replacement drugs, such as AndroGel and Testim. Sales of easy-to-use topical testosterone drugs are expected to triple within the next five years as more and more men perceive them as a fountain of youth that can restore energy, muscle, strength, and libido.
As testosterone drug sales soar, so does the risk of secondary exposure to the drugs by women and children, who may suffer adverse effects after coming into contact with the patient’s skin and/or clothing. Women exposed to topical testosterone drugs may experience growth of hair in new places on the body and/or acne. Children may experience enlarged genitals, growth of pubic hair, increased erections, increased sexual desire, and aggressive behavior. While most of these symptoms typically go away after exposure to testosterone gel ceases, children could exposed to the drugs can be permanently harmed by exposure.