Keeping slim and trim is not only a matter of beauty, preventing obesity is crucial for the physical, mental and fiscal welfare of our society. As obesity rates increase so does physical and mental illness and their associated costs. The fundamental changes in how we live a healthy life can start today. By measuring the impact of activities of daily living on energy expenditure, Prof. James Levine's NEAT theory shows us why calories that people burn in their everyday activities are far more important in obesity than we previously imagined. According to Prof. Levine, low NEAT and sedentary living go hand-in-hand while NEAT-active living may be the key to preventing and reversing obesity.