Obesity is a growing public health problem worldwide with more than one billion overweight and 300 million obese according to the WHO. Obesity contributes to serious diseases such as diabetes and cardiovascular disease. Several reports have shown that people who spend much of the day sitting are at increased risk of obesity and diabetes. Our results suggest that increased leg loading, which occurs when standing up, may lead to more activation of a 'body wave' in the weight-bearing long tubular bones, which in turn leads to more activity in an anti-obesity system and hence reduced weight. There is already a well-known system that aims to keep fat mass constant. The anti-obesity hormone leptin is released into the bloodstream from adipose tissue in proportion to the size of the fat mass. Leptin exerts a negative feedback loop in the brain leading to reduced appetite and obesity. Unfortunately, for unknown reasons, most obese people are insensitive to leptin's anti-obesity effect. We have now shown in the prestigious American Academy of Sciences journal PNAS that inserting weights into the abdominal cavity or under the skin of obese mice reduces their food intake, body weight and fat mass independently of leptin. This effect seems to involve a specific cell type in the long tubular bones. We now want to study the exact mechanism of how the 'body wave' in the legs affects fat mass and appetite, probably via an effect on the brain. We also want to investigate the importance of this novel system for fat regulation in humans.