The human body was designed for life forty thousand years ago, when the ability to store energy in times of plenty meant the difference between life and death during famine. This protective mechanism is a source of trouble when food, in unlimited quantities, is readily available. This is evident in the increasing prevalence of excessive weight in humans in modern times, particularly in Western cultures. While excess weight is just an exaggeration of a normal body, the storage of energy for future is properly classified as a health problem. This is because excessive amounts of storage fat may interfere with the normal physiology of the body. Excess storage fat is directly related to the increasing prevalence of Type II diabetes. It contributes to fatigue, high blood pressure, menstrual disorders, infertility, digestive complaints, low levels of physical fitness and to the development of some cancers. The social costs of excess fat that include decreased productivity, discrimination, depression, and low self-esteem, are less easily described and measured. Worldwide, it has reached epidemic proportions in the last thirty years, affecting both sexes and all ethnic, age, and socioeconomic groups. More than 50% of adults in the United States, for example, currently fall into over weight classifications, and 22% of preschool children are classified as overweight. The increasing prevalence of excess weight heralds spiraling health care costs in the near future for those who have the problem.