A portion is how much food you choose to eat at one time, whether in a restaurant, from a package, or at home. A serving, or serving size, is the amount of food listed on a product’s Nutrition Facts, or food label (see Figure 1 below).
Different products have different serving sizes, which could be measured in cups, ounces, grams, pieces, slices, or numbers—such as three crackers. A serving size on a food label may be more or less than the amount you should eat, depending on your age, weight, whether you are male or female, and how active you are. Depending on how much you choose to eat, your portion size may or may not match the serving size.
As a result of updates to the Nutrition Facts label External link in May 2016, some serving sizes on food labels may be larger or smaller than they had been before (see Figure 2 below). For instance, a serving size of ice cream is now 2/3 cup, instead of 1/2 cup. A serving size of yogurt is 6 ounces rather than 8 ounces. The U.S. Food and Drug Administration (FDA) changed some food and beverage serving sizes so that labels more closely match how much people actually eat and drink.