Effect of Weight Loss on Disease

Obesity has a negative effect on the health of patients and is becoming an increasing problem worldwide. Morbid obesity in particular affects most major organ systems and is implicated in several of the most lethal medical conditions: diabetes, myocardial ischemia, hypertension, and many cancers. Weight loss has been shown to reverse many of the comorbidities associated with obesity, with a resulting positive benefit to the patient’s health and quality of life. Achieving substantial and persistent weight loss is difficult and, to date, surgery has been the only truly effective option for treatment of obesity. Obesity has effects on multiple organ systems. Whereas some effects are permanent, many can be reversed if the patient loses a substantial amount of weight. This includes the endocrine system (diabetes), the musculoskeletal system (degenerative joint disease), and the cardiovascular system (hypertension, congestive heart failure, hypercoagulability and stroke). Dieting and exercise can be effective strategies for the moderately overweight but have a high failure rate (>90%) in the morbidly obese. Medical treatments have a mixed history and, in general, have only moderate efficacy and high side effect profiles. Surgery has been shown to be the most effective long term weight-loss strategy but is a relatively high-risk endeavor in this patient population. The laparoscopic gastric bypass is currently the most widely used bariatric surgery, achieving around 75% excess weight loss at 5-yr follow-up.