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Learn It

Portion Distortion and Serving Size

A portion is the amount of food that you choose to eat for a meal or snack. Portions can be big or small, it depends on how much you choose to eat.

A serving is a measured amount of food or drink, such as one slice of bread or 8 ounces of milk.

Some foods that people consume as a single portion actually contain multiple servings. For example a 20-ounce soda has 2.5 servings and a 3-ounce bag of chips has 3 servings. Nutrition recommendations use serving sizes to help people know how much of different types of foods they should eat to get the nutrients they need.

The Nutrition Facts label on packaged foods lists a serving size. The serving sizes on packaged foods are not always the same as those included in nutrition recommendations. However, serving sizes are standardized to make it easier to compare similar foods.

To get an idea of how large recommended serving sizes really are, check out the NHLBI Serving Size Card. For help on using the Nutrition Facts label, visit the Food and Drug Administration (FDA) Web site at

Portion Distortion

Balancing your family's energy is challenging today because average portion sizes have grown over the past 20 years. It's challenging to find a small portion in a restaurant these days. The plate arrives and there's often enough food on it for two or even three people.

These ever-larger portions are changing what Americans think of as a "normal" portion, and that affects how much we eat at home as well. Cutting back on portion size is a great way to help keep calories in check. It doesn't take lots of calories to disturb your energy balance.

Still aren't sure how much portion sizes have changed? Check out these examples:

20 Years Ago Today
  Portion Calories   Portion Calories
Bagel 3'' diameter 140 Bagel 6'' diameter 350
Cheeseburger 1 333 Cheeseburger 1 590
Spaghetti w/meatballs 1 cup sauce
3 sm meatballs
500 Spaghetti w/meatballs 2 cups sauce
3 lg meatballs
Soda 6.5 ounces 82 Soda 20 ounces 250
Blueberry muffin 1.5 ounces 210 Blueberry muffin 5 ounces 500

For more eye-opening examples, check out NHLBI's Portion Distortion Web site at

Help your family balance their ENERGY IN by making smart food choices when eating at home and in restaurants. Visit the Live It section for more tips for eating at home or in restuarants.


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