Over the centuries people have become taller, heavier, and stronger. One of the major reasons for this is the increasing supply of calories in our diets. In earlier times, weight gain was extremely beneficial for health, well-being, and lifespan, but in 2012 we are at a point where weight gain has gone too far and is now detrimental. We are facing an overeating epidemic and the adverse health effects of obesity. This article discusses some of the causes of obesity and the factors affecting it.