A study on mice found that obesity induces chronic alterations in the brain, resulting in reduced sperm count.

To mimic human obesity, researchers at the University of California-Riverside fed mice a high-fat diet.

Their findings revealed that the mice’s brains had fewer connections between neurons and fewer receptors, which normally notify the brain that there is enough energy and that it should stop eating.

“This could explain why we don’t cut back on our calorie intake,” said Djurdjica Coss, a biomedical sciences professor at the School of Medicine and lead author of the study published in the Journal of Neuroscience.

According to Coss, the hypothalamus-pituitary-gonadal axis regulates reproductive function, and obesity disrupts it predominantly in the brain rather than the testes or pituitary.

Obesity leads to lower pituitary hormone levels, which diminish testosterone and sperm production.

In mice on a high-fat diet, the researchers discovered less synaptic connections in neurons that regulate reproduction, which is similar to human systems.

Obesity affects millions of people globally and is linked to health problems such as cardiovascular disease and type 2 diabetes.