TUESDAY, March 3 (HealthDay News) -- The more obese a man, the greater his hormonal changes and the worse his sex life, a new study finds.

On the up side, the study's authors found that gastric bypass surgery can help reverse those ills.

"Previous studies have found that obesity is correlated to lower sperm count and can be associated with infertility, but we wanted to know if obesity was biologically associated with an unsatisfying sex life, and if so, could it be reversible," the study's lead author, Dr. Ahmad Hammoud, of the University of Utah, said in an Endocrine Society news release. "Our results show that the answer to both questions may be yes."

The researchers checked the weight, body mass index (BMI) and reproductive hormone levels of 64 obese men at the start of the study and again two years later, after some of them had what's known as Roux-en-Y gastric bypass surgery. The participants also filled out questionnaires about the quality of their lives.

"In our study population, we found that lower testosterone levels and diminished ratings for sexual quality of life were correlated with increased BMI," Hammoud said. "Subjects who lost weight through bariatric surgery experienced a reduction in estradiol [hormone] levels, an increase in testosterone levels and an increase in ratings of sexual quality of life."

The study will appear in the Journal of Clinical Endocrinology & Metabolism.

The findings highlight a link between sexual quality of life and hormonal measures independent from weight, Hammoud said. He added that further studies are needed to determine a cause-and-effect relationship.

More information

The U.S. National Institute of Diabetes and Digestive and Kidney Diseases outlines the health risks of being overweight.