The epidemic of obesity has highlighted the extent of the risks associated with this disease. The risks arise from the increased mass of fat tissue, as well as the products produced by the increased number and size of fat cells in obese individuals. Psychosocial dysfunction, obstructive sleep apnea, and osteoarthritis can be a direct result of increased fat mass. Other diseases associated with obesity result from the metabolic consequences of enlarged fat cells. Diabetes, gallbladder stones, high blood pressure, liver disease, coronary artery disease, cerebrovascular disease, certain types of cancers, and infertility can all be traced in part to the increased secretion of inflammatory and coagulation molecules from fat cells. Finally, obesity also increases overall mortality. It is clear from this review that the morbidity and increased mortality of overweight and obesity is substantial and should prompt further attention towards the need for appropriate weight management in health care.