Obesity leads to and exacerbates many serious disorders, including hypertension, dyslipidemia, cardiovascular disease, non-insulin-dependent diabetes mellitus, gallbladder disease, respiratory dysfunction, gout, and osteoarthritis. Many short-term studies have shown that weight loss can ameliorate or, in some cases, reverse such disorders. Fewer long-term studies-defined as those whose combined acute intervention and follow-up phases extend for at least 1 year-of the therapeutic benefits of weight loss on specific disorders have been undertaken. Those long-term studies that have been performed tend to confirm the results of briefer studies. Even when weight loss has been comparatively modest or some degree of weight regain has occurred, weight loss is generally associated with a decrease in risk factors and the alleviation of clinical symptoms.