Activity Four: Serving Sizes, of the instructional unit, Food and Fitness, helps students learn how to estimate portions and use serving size information provided on Nutrition Facts labels.

Science concepts covered in this activity include the following.

• Objects have observable properties that can be measured.

• Serving sizes on food labels can help guide food choices.

The complete Food and Fitness Activities Guide for Teachers may be downloaded as a PDF file from the Teacher Resources menu on BioEd Online: http://www.bioedonline.org/resources/nsbri.cfm

Viewing  this presentation fulfills part of the requirements for completing the Virtual Workshop on Energy, Food and Nutrition (“Food and Fitness”), offered for professional development contact hours on BioEd Online.

Funding for development of the Food and Fitness unit and accompanying online professional development was provided by the National Space Biomedical Research Institute (NSBRI), a consortium of leading biomedical research centers funded by the National Aeronautics and Space Administration (NASA). Visit the following sites for more information about these organizations.

Center for Educational Outreach, Baylor College of Medicine: http://www.ccit.bcm.tmc.edu/ceo/
National Space Biomedical Research Institute: www.nsbri.org
National Aeronautics and Space Administration: http://www.nasa.gov

Portion sizes of convenience and fast foods steadily have increased in the United States over the past thirty years (Nielsen and Popkin, 2003). In many cases, the portions served and eaten actually contain several “serving sizes,” as defined by Food Pyramid or even the Nutrition Facts labels on foods. For example, a large baked potato corresponds to three servings of carbohydrates. A large bagel delivers the equivalent of four bread servings.

Sometimes, the serving sizes listed on “Nutrition Facts” labels of food packages are different than the serving sizes listed by other guides, such as the USDA Food Pyramid. This differences arise because information on the Food Pyramid is designed to help people meet daily nutrient recommendations by providing relatively few, easy-to-remember serving sizes for each of the food groups. Nutrition Facts labels, on the other hand, provide detailed nutritional information that enables consumers to compare similar foods and make selections based on nutritional content. Ideally, the two sources of information should be used together to make appropriate food choices.

The complete Food and Fitness Activities Guide for Teachers may be downloaded as a PDF file from the Teacher Resources menu on BioEd Online: http://www.bioedonline.org/resources/nsbri.cfm

Food labels and other guides often use “serving size” to describe a recommended single portion of a food. Serving sizes are different for various kinds of foods (meats, fruits and vegetables, etc.), liquid and solid foods, and cooked versus raw foods. In many case, the amount specified as a serving size for a particular food is smaller than the amount typically eaten.

To help students learn to estimate appropriate serving sizes, challenge groups of students to predict appropriate servings sizes of a vegetable, snack food, cereal and liquid, and to record their predictions. Next, have students actually measure out the quantities that they predicted. You may need to explain that food portions in the US typically are measured in “cups.” Show students examples of measuring cups for liquid and solid foods.

As an extension to this activity, have students investigate the metric equivalents of cups for liquids (liters) and solids (grams).

The complete Food and Fitness Activities Guide for Teachers may be downloaded as a PDF file from the Teacher Resources menu on BioEd Online: http://www.bioedonline.org/resources/nsbri.cfm

Nutrition Facts labels on packaged foods can help consumers make better food choices. A Nutrition Facts label lists the serving size of the food and the number of servings per container. In addition, the label reports the amounts of nutrients present in grams and as a percentage of Daily Values for a 2,000 calorie diet. According to the USDA Center for Nutrition Policy and Promotion, Nutrition Facts label serving sizes are more or less based on amounts customarily eaten at one time, and do not necessarily correspond to serving sizes recommended by the Food Pyramid.

Serving Sizes on labels are reported in one of three ways. For bulk materials, such as cereals and flour, the labels use common household terms, such as cup, tablespoon, teaspoon or fluid ounce. For products that usually are divided into pieces, such as cake or pizza, the serving size is a fractional amount of the whole (for example, 1/4 pizza). Products that come as units, such as eggs, cookies or sliced products, are listed as the number of whole units that closely approximates a reference amount. For example, if a cookie has a reference amount of 30 grams, the serving size on a package of cookies that weigh about 30 grams each would list a serving size as “one cookie (30 grams).”

The complete Food and Fitness Activities Guide for Teachers may be downloaded as a PDF file from the Teacher Resources menu on BioEd Online: http://www.bioedonline.org/resources/nsbri.cfm