Overeating (or over-eating) is eating food more than the body needs. There is a relationship between the energy that an organism uses and the amount eaten. Eating more leads to weight gaining and often obesity. It may be regarded as an eating disorder.
One consequence of overeating is weight gain, and excess weight may cause blood pressure to rise. In turn this makes illness and even death more likely.
The problem is very difficult to reverse: losing weight is often attempted, but rarely succeeds. Weight lost is usually rapidly replaced. Diets are famously unsuccessful. Obesity is the end product of overeating.
Some difficult facts are known. Poorer families tend to eat worse food than better-off families. Children learn from the experiences in their families. Once established, habits are hard to break. In 2013, several medical societies, including the American Medical Association and the American Heart Association, classified obesity as a disease.
- Obesity and overweight Fact sheet N°311. WHO. January 2015. 
- Pollack A (18 June 2013). "A.M.A. Recognizes Obesity as a Disease". New York Times. Archived from the original on 24 June 2013.
- Weinstock, Matthew (21 June 2013). "The Facts About Obesity". H&HN. American Hospital Association. Retrieved 24 June 2013.