Serving size

Abstract: The Food Guide Pyramid Automated Analysis System (FGPAAS) would classify foods under the appropriate categories of the Food Guide Pyramid (FGP). Further, it would provide an estimation of the serving size(s) of the food group(s) for the food being analyzed, per the FGP guidelines provided by the United States Department of Agriculture (USDA). In the development of this automated analysis tool an extensive database of foods and their nutrients was used. Principles of food science and food composition were applied in the development of this analysis system. A number of factors were taken into consideration. Foods, as they are consumed, can be classified as single foods (SF) and combination foods (CF). The classification of SF consists of foods that can be categorized under any one food group of the FGP. The CF consist of two or more foods that can be categorized under one or more food groups of the FGP. The ratio of the constituent foods in the CF could vary from one food to the other. The above issues are further complicated by the fact that all foods undergo changes in their nutrient composition when they are prepared or processed. This could mean an unintentional loss of nutrients or, the removal of nutrients such as fat. Also, processing could involve the addition of nutrients such as vitamins and minerals for enrichment or fortification. Or the addition of non nutritive substances to the food. The development of the FGPAAS involved an in-depth study of the nutrient composition of a number of foods under the various food groups of the FGP. These were compared with the nutrient outlines provided by the USDA. To comply with the USDA guidelines for the FGP, the nutrient outlines provided by the USDA were used as the basis for the analysis. In addition, special subgroups were created to facilitate accurate analysis of all foods. Certain key nutrients were established for each food group and a methodology for the analysis was established. A system was then developed for the automated analysis of SF and CF. The FGPAAS, is presently being tested. When instituted, SF would be classified with precise serving sizes under the appropriate food group and CF would be broken into its constituent foods and provide cogent serving sizes for the respective food groups. As a tool, the FGPAAS can be used in the analysis of presently available foods or those that are being developed, given the nutrient composition of the food. It can also be used for the analysis of foods of any ethnic origin. The FGPAAS would be useful in the analysis of diets and can aid in the delivery of nutrition education, to encourage and to improve food choice practices.

Abstract: The greater energy content of larger food portions could be contributing to the increasing prevalence of overweight. Prevention guidelines recommend ″sensible" portion sizes but do not define them. The US Department of Agriculture (USDA) defines standard serving sizes for dietary guidance, and the Food and Drug Administration (FDA) defines standard servings for food labels. To use these standards in counseling, nutritionists must know the sizes of portions available in the marketplace. We determined marketplace portion sizes, identified changes in these sizes with time, and compared current marketplace portions with federal standards. Most marketplace portions exceed standard serving sizes by at least a factor of 2 and sometimes 8-fold. Portions have increased over time; those offered by fast-food chains, for example, often are 2 to 5 times larger than the original size. The discrepancy between marketplace portions and standard servings suggests the need for greater emphasis on the relationship of portion size to energy intake as a factor in weight maintenance. J Am Diet Assoc. 2003;103:231-234.