BOSTON, June 9 (UPI) -- People who are obese and eat a high-fat diet may injure the neurons, or nerve cells, in a key part of the brain that controls body weight, U.S. researchers say.

Dr. Joshua Thaler of the Diabetes and Obesity Center of Excellence at the University of Washington in Seattle and colleagues studied the brains of rodents for the short-term and long-term effects of eating a high-fat diet. After giving groups of six to 10 rats and mice a high-fat diet for periods from one day to eight months, the researchers performed detailed analyses on the animals' brains.

The researchers detected damage to, and eventual loss of, critical weight-regulating neurons.

"The possibility that brain injury may be a consequence of the over consumption of a typical American diet offers a new explanation for why sustained weight loss is so difficult for most obese individuals to achieve," Thaler says in a statement.

After the first three days of consuming fat content similar to that of the typical U.S. diet, rats consumed nearly double their usual daily amount of calories -- and rats and mice fed the high-fat diet gained weight throughout the study, Thaler says.

If medicines can be developed to limit this neuron injury during overeating, they may be effective in combating the obesity, Thaler says.

The findings are being presented at The Endocrine Society's 93rd annual meeting in Boston.