Optimal management of overweight and obese patients requires a combination of diet (i.e., reduced caloric intake), exercise, and behavior change. In addition, some patients will eventually require medication or bariatric surgery. Before starting any treatment program, the patient’s risk of being overweight should be assessed. A risk-benefit assessment can then be used to select a treatment approach. The choice of treatment depends on several factors, including the degree of overweight or obesity, comorbidities, and patient preferences.
Weight loss of 5 to 7 percent has many health benefits and should be the initial weight loss goal.
Weight loss is directly related to the difference between an individual’s energy intake and energy expenditure. Reducing caloric intake to below expenditure results in a predictable initial rate of weight loss, which is associated with energy deficiency. Significant differences exist between individuals, so close monitoring of energy intake is critical. Patients should be educated that weight loss itself can reduce energy expenditure and that weight is expected to stabilize without further reductions in energy intake.
The goal of dietary therapy is to reduce the total number of calories consumed. We recommend dietary choices of healthy foods, such as the Dietary Approaches to Stop Hypertension (DASH) or the Mediterranean-style diet, rather than focusing on specific nutrients (Level 2B). A diet that emphasizes reducing refined carbohydrates, processed meats, and foods high in sodium and trans fats; moderate consumption of unprocessed red meat, poultry, eggs, and milk; and high intakes of fruits, nuts, fish, vegetables, vegetable oils, minimally processed whole grains, legumes, and yogurt are preferred.
Dietary habits are a significant predictor of weight loss, independent of diet type. Behavior change strategies are important to improve dietary adherence to any type of diet.
If a low-carbohydrate diet is chosen, healthy choices of fats (mono- and polyunsaturated fatty acids) and proteins (fish, nuts, legumes, and poultry) should be encouraged. If a low-fat diet is chosen, then fat reduction should be accompanied by an increase in healthy carbohydrates (fruits, vegetables, whole grains).
Although many people are successful in losing weight through diet, most subsequently regain most or all of the weight they have lost. Since long-term adherence to a weight loss diet is probably the most important determinant of success, the best weight loss diet will depend on preference and personal factors.