Diet and obesity.

PURPOSE OF REVIEW: Obesity continues to increase in the United States and worldwide. There is controversy surrounding different dietary patterns used to promote weight loss, and none has emerged as clearly more effective. This paper briefly reviews the factors that influence energy intake and dietary treatments used to promote weight loss. RECENT FINDINGS: Increasing portion size, eating away from home, and consuming a variety of high-energy dense foods appear to increase energy intake. Hormonal influences on diet continue to be explored. Very-low-calorie diets and low-carbohydrate diets lead to greater initial weight loss, but long-term results are no better than more moderate calorie-restricted diets. A program using meal replacements appears to lead to weight loss slightly greater than calorie-restricted diets and offers one option to treat obesity. Dietary patterns low in energy density and glycemic index have potential in treating obesity and should be studied further. SUMMARY: Clearly, a dietary pattern that prescribes a lower total energy intake is necessary for weight loss, and this pattern should be sustainable to maintain weight loss. Although many dietary programs can achieve short-term loss of weight, dietary treatment should be recommended that emphasizes lifestyle changes and is consistent with other dietary guidelines to promote long-term health. Features consistent with this are a dietary pattern low in total calories, saturated fat, and refined carbohydrate; moderate in whole grains; and high in low-energy dense vegetables and fruits. Future studies should explore dietary strategies and combination therapies that contribute to weight loss, long-term weight maintenance, and improved health.