New Delhi, July 19 (IANS): Obesity causes chronic changes in the brain, leading to lower sperm count, according to a study in mice.

The study led by University of California-Riverside researchers used mice fed a high-fat diet to imitate human obesity.

Their findings showed that the mice's brains had fewer connections between neurons and fewer receptors, which ordinarily alert the brain that enough energy is available and to 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.

Coss added that reproductive function is regulated by the hypothalamus-pituitary-gonadal axis, which is disrupted by obesity, primarily affecting the brain rather than the testes or pituitary.

In obesity, lower hormone levels from the pituitary result in reduced testosterone and sperm production.

The research found fewer synaptic connections in neurons regulating reproduction in high-fat diet-fed mice, which parallels human mechanisms.

Obesity impacts millions worldwide and is linked to health issues like cardiovascular disease and Type 2 diabetes.