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Tools and Equipment of Science

Author(s): Roberta Anding, MS, RD/LD, CDE
Showing Results for: teaching Return to Presentation

Portion Sizes

Many Americans overestimate portion sizes. When teaching portion sizes, it can be helpful to have students estimate the number of servings of juice or other drinks contained in a typical drinking glass. Even though a serving of fruit juice typically is four ounces, most adolescents drink from glasses that contain between 10 and 16 ounces of liquid. Soft drinks are a major source of hidden added Calories in adolescents’ diets.

Restaurants often serve quantities of food that exceed a single portion size. For example, a typical “super-sized” meal can contain as many as 1,500 to 2,000 Calories—almost an entire day’s worth of Calories—in a single meal or snack. A sedentary lifestyle also contributes to obesity. In particular, television viewing has been linked to weight gains and obesity among young people. Researchers have hypothesized that television viewing contributes to obesity by displacing physical activity, increasing calorie consumption while watching (including the effects of advertising) and reducing resting metabolism (Robinson, 2001).