 What is obesity and what causes it? Obesity is a medical condition where a person has accumulated an excessive amount of body fat that may impair health. A person is considered obese if their body weight is at least 20% higher than it should be. If a person's body mass index, a statistical measurement derived from their height and weight, is 30 or over they are considered obese, too. But what causes obesity? The main cause of obesity and overweight is an energy imbalance between the consumed calories, through food and liquids, and the burned calories, through workout and other daily activities. That's because people are eating more fat and sugar while reducing their physical activity to a minimum, thanks to sedentary work, increasing urbanization and more comfortable ways of transport. But that's not it. Obesity can also be caused by a lack of sleep, faulty genes and hormones or certain medication. In addition, new research indicates that it gets more and more difficult to lose weight, the more weight a person carries. The best treatment of obesity is eating healthy food and increasing physical activity. Unfortunately it can't be guaranteed to result in weight loss. Unlike anorexia, obesity isn't considered a disease yet, which makes treatment very expensive for the person affected. Always remember, being obese isn't necessarily the person's fault. Don't bully or mock someone because of it. Be gentle. Good love, not hate.