A class of drugs used to treat diabetes also appears to help patients lose weight by changing how the brain responds to food, a new study suggests.

Researchers have been trying to learn how gut-hormone based medications called GLP-1 receptor agonists also help people with type 2 diabetes shed excess pounds.

A Dutch team said the drugs may reduce cravings and increase satisfaction while eating. The researchers looked specifically at the injectable GLP-1 receptor agonist exenatide (Bydureon, Byetta).

Their findings were to be presented Tuesday at the American Diabetes Association (ADA) annual meeting in Boston.

"When you eat, there are several hormones released. GLP-1 is one of them," Dr. Liselotte van Bloemendaal, a Ph.D. student at the Diabetes Center, VU University Medical Center in Amsterdam, Holland, said in an ADA news release.

"These hormones relay information to the central nervous system about nutritional status to regulate appetite. Using functional MRIs [which measure brain activity by detecting changes in blood flow], we looked at the reward centers in the brains of obese individuals with and without type 2 diabetes and measured the response to the anticipation of and drinking of chocolate milk while being given GLP-1 receptor agonist intravenously versus placebo," she explained.

When given the drug, the brain didn't anticipate the food reward as much. The researchers said this could lead to reduced cravings.

The drug also seemed to increase the feeling of reward from food while people were eating, which might reduce overeating, according to van Bloemendaal.

The findings may lead to new treatments for obesity, she said.

Van Bloemendaal also wants to determine whether these drugs can reduce cravings for drugs, alcohol and nicotine.