Obesity and impaired glucose tolerance are associated with a greater risk for a number of conditions, including insulin resistance, diabetes mellitus, hypertension, dyslipidemia, coagulation abnormalities, inflammatory markers, and coronary heart disease. Lifestyle changes can delay or prevent the development of type 2 diabetes in patients with obesity and impaired glucose tolerance. The risks improve with weight loss and increased physical activity. A decrease of 7% to 10% or more from baseline weight can have a significant effect. This has now been documented in a number of randomized, controlled studies.