A “portion” is how much food you choose to eat at one time, whether in a restaurant, from a package, or in your own kitchen. A “serving” size is the amount of food listed on a product’s Nutrition Facts. Sometimes, the portion size and serving size match; sometimes they do not. Keep in mind that the serving size on the Nutrition Facts is not a recommended amount of food to eat. It is a quick way of letting you know the calories and nutrients in a certain amount of food.