摘要：Because restaurants routinely serve food with more calories than people need, dining out represents a risk factor for overweight, obesity, and other diet-related chronic diseases. Most people lack the capacity to judge the caloric content of food and there is limited evidence that people make use of calorie-labeling information when it is available. Standardized portion sizes would not preclude people from eating as much as they want, but would make the amount they are getting fully transparent. We describe the potential benefits and means of implementing a system of standardized portion sizes that might facilitate a healthier diet among the US population. A robust finding in multiple experiments, in both natural and laboratory settings, is that when people are served more food than they need, they eat more than they should. 1 Furthermore, there is considerable evidence that many people cannot recognize when portions are increased and cannot rely on internal satiety signals to indicate when they have eaten enough. 2 Substantial increases in energy consumption over the past four decades have occurred in both children and adults without compensatory increases in the level of energy expenditures. 3 Food away from home is a major contributor to excess calories consumed, contributing more than one third of all calories, while constituting fewer than one third of all eating occasions. 4,5 Data from the 1999–2000 National Health and Nutrition Examination Survey indicate that the average person eats commercially prepared food 2.8 times per week, and since then the frequency of dining out has continued to grow. 6 Because the calories in the portions of food prepared away from home are substantially higher than what is generally prepared at home, dining out has become a major risk factor for obesity. 7 One public health effort to reduce the risk of consuming too much food away from home has been to mandate menu calorie labeling. Although menu labeling was intended to help people assess their caloric intake, a review indicated that calorie labels do not consistently influence the choices of most people, in part because people do not notice them, but also because many do not understand their significance. 8 To mitigate the risk that dining out contributes to chronic diseases, a more effective approach should make serving size a matter that cannot be ignored. One solution is to create and implement a system of standardized portions for people who are eating out, so that all foods are served in quantities that are appropriate for consumption by one person at a single sitting. In this article, we describe the potential benefits and means of implementing a system of standardized portion sizes that might assist the US population in obtaining a healthier diet.
