Type 2 diabetes, cardiovascular disease, and hypertension are comorbities associated with obesity. Treatment and prevention strategies for these comorbidities of obesity are often assumed to be the same-weight loss. Although many persons may lose weight initially, recidivism is a major concern. Therefore, medical nutrition therapy for obese persons with comorbidities should be refocused from weight loss to attaining and maintaining metabolic parameters-normal blood glucose levels, optimal lipid levels, and blood pressure levels within normal limits. Moderate weight loss is only one lifestyle strategy that can be recommended. Research has also supported other lifestyle strategies, including becoming more physically fit. In type 2 diabetes, a restricted energy diet even without weight loss, spacing of meals throughout the day, and fat intake modifications have been shown to improve glycemia. Dyslipidemia can be improved by reducing or changing the fat content of the diet. Blood pressure levels can be reduced by a diet high in fruits and vegetables and low in fat. Research is underway to determine if weight loss can prevent chronic diseases; however, once comorbidities are present, lifestyle strategies should be directed toward the improvement of metabolic parameters associated with the comorbidity. J Am Diet Assoc. 1998;98(suppl 2):S39-S43.