The word epidemic conjures up alarming images: plague, pestilence, destruction and death. We are not used to lumping obesity in with such disasters, but the recent increase in the global prevalence of obesity qualifies as an epidemic. Obesity claims an increasing number of lives worldwide; discouraging statistics around in both the medical and popular press. The obesity epidemic is recognized by the World Health Organization as one of the top 10 global health problems. 

The implications of excess weight are sobering enough to encourage action. In the United Kingdom, almost one in three residents is trying to lose weight. In the United States, one in five men and one in three women are on some type of diet. Additional behavior studies show that nearly as many people are actively attempting to maintain their current weight. 

People often try to control their weight by using more than one method. On average, dieters try one approach or another for about six months over a period of several years. Many consumers, who have tried to lose weight by restricting calories, find themselves trapped in the yo-yo effect.

Clinical studies demonstrate that even a modest amount of weight loss (5-10 % of the body weight) may prevent significant health problems, such as type II diabetes.