High-fat foods could be making men, well, less manly, according to a new study from the University at Buffalo.

Obese boys between the ages and 14 and 20 showed significantly lower levels of testosterone than lean boys the same age, the study concludes.

Researchers monitored blood samples from 25 boys with high BMIs and 25 boys with healthy BMIs, and they found that subjects on the high end were likely to produce 40 to 50 percent less testosterone, increasing their chances of becoming impotent or infertile adults.

“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,” Paresh Dandona, professor in the department of medicine, said in a UB news release. “The implications of our findings are, frankly, horrendous because these boys are potentially impotent and infertile.”

“The message is a grim one with massive epidemiological implications,” Dandona added.

Not only do higher fat concentrations in young men have reproductive consequences, but these boys are more likely grown up to have less muscle tissue and insulin resistance, which can lead to diabetes.

Dandona and fellow researchers intend to study a larger sample and they hope to determine whether weight loss could help formerly obese boys’ regain testosterone.

Excess fat, which is known to cause a variety of health issues, is also linked to higher cancer rates. the Telegraph recently reported that about 18 percent of cancer cases in the UK could have been prevented if those suffering from cancer had healthier lifestyle habits.

“Through keeping levels of body fat low, a lot of people will avoid getting cancer in the first place – forestalling the pain and anguish associated with the disease,” Alan Jackson, professor of human nutrition at the University of Southampton, told the Telegraph.