Published November 19, 2012
Obese teen boys have up to 50 percent less testosterone than lean boys, significantly increasing their risk of impotence and infertility in later life, according to the results of a new UB study.
“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,” says first author Paresh Dandona, MD, PhD.
Dandona and his colleagues were the first group to report low testosterone levels in obese, Type 2 diabetic adult men, results they confirmed in a 2010 study.
“We were surprised to observe a 50 percent reduction in testosterone in this pediatric study because these obese males were young and were not diabetic,” says Dandona, SUNY Distinguished Professor of medicine and chief of the endocrinology and metabolism division.
The study results send a grim message with major epidemiological consequences, he adds.
“The implications of our findings are, frankly, horrendous because these boys are potentially impotent and infertile.”
The UB researchers measured total and free testosterone and estradiol concentrations in morning fasting blood samples of 25 obese and 25 lean males between the ages of 14 and 20.
The study’s results must be confirmed with a larger number of subjects, Dandona says.
In addition to the reproductive consequences, the absence or low levels of testosterone increases the tendency toward abdominal fat and reduced muscle, he explains. This leads to insulin resistance, which contributes to diabetes.
Researchers already have determined that testosterone levels return to normal when obese adult men undergo gastric bypass surgery.
Next, Dandona and his colleagues plan to study whether losing weight via lifestyle changes or pharmaceutical intervention can increase testosterone levels in obese teen boys.
Other co-authors are: