Eating a highfat diet even for a short period may change the brain in ways that makes it harder to lose weight, a new study has found.

In experiments on rodents, a team from the University of Washington School of Medicine found that when placed on a high-fat diet, animals developed injuries to a brain area called hypothalamus that controls the urge to eat and sends signals to stop eating when full. Signs of similar damage in the same brain area in obese people have also been found, the researcher said.

"Within 24 hours of switching rodents to a highfat diet, we found injury in the hypothalamus area," study co-author Michael Schwartz, an endocrinologist at the University said.

According to the researchers , obesity causes inflammation in the tissues and organs. This isn't the same type of inflammation you get during an allergic reaction. Instead it's a low level of inflammation that persists in the body.

The team speculated that obesity might be linked with inflammation in the hypothalamus , "which may prevent it from responding to hormones like insulin that regulate our body weight" , said co-author Joshua Thaler.