London, Dec 28 (IANS): Human body consists of an internal body weight sensing system that operates like bathroom scales, registering body weight and signalling the brain to reduce food intake, researchers have found.

The system, which regulates weight gain by calculating body weight and fat mass, could lead to a better understanding of the causes of obesity as well as new anti-obesity drugs.

The results also explain why several studies have coupled sitting habit with obesity and bad health. It is because the "internal body scales give an inaccurately low measure when you sit down. As a result you eat more and gain weight," the researchers said.

"We have found support for the existence of internal bathroom scales. The weight of the body is registered in the lower extremities. If the body weight tends to increase, a signal is sent to the brain to decrease food intake and keep the body weight constant," said John-Olov Jansson, Professor at Sahlgrenska Academy, University of Gothenburg in Sweden.

Further, the results demonstrate that the weight sensing system regulates fat mass independently of leptin -- a weight loss hormone. It is possible that leptin combined with activation of the internal body scales can become an effective treatment for obesity, the researchers said.

For the study, published in the journal Proceedings of the National Academy of Sciences (PNAS), the team performed experiments on obese rodents that were made artificially heavier by loading with extra weights.

The animals lost almost as much weight as the artificial load. The extra weights caused body fat to decrease and blood glucose levels to improve.