How to gauge food portion sizes

One of the most important things you can do to achieve and maintain a healthy weight is to become aware of “portion sizes.” That refers to the actual amount of food you eat at a single time. It isn’t necessarily the same as the “serving size”—or standardized amount of food—that you see on a Nutrition Facts label.

A portion of food can be either bigger or smaller than a serving size. For example, your portion of whole-wheat pasta might be one cup, but that’s actually two servings (one serving = ½ cup). Examples of serving sizes include:

  • one slice of bread
  • ½ cup of cooked vegetables
  • ½ cup of fruit
  • 1½ ounces of hard cheese (cheddar, swiss, parmesan)
  • 8 oz milk
  • 3 oz of meat, fish, or poultry

Watching portion sizes is especially important if you’re trying to lose weight. In any case, it isn’t always practical to use a measuring cup when you’re dishing up a plate of food or spreading peanut butter on your toast.

A more realistic way to gauge your portion sizes is to “eyeball” them—that is, to visually compare your food portions to a familiar frame of reference. The infographic on the right uses your hand as your guide to keep portion sizes in check. Of course, your hand might be larger or smaller than someone else’s, but your hand size generally equates to your body size and, as a result, your portion needs. What’s more, it’s one measuring device you’ll always have on hand.

Your handy guide to portion sizes: Your fist about equals a one-cup serving of milk or raw vegetables. Your thumb about equals one 2-tablespoon serving of peanut butter or salad dressing. Your cupped palm about equals one half-cup serving of cooked fruit, vegetables, beans, or starch. Your thumbnail about equals a one-teaspoon serving of butter or margarine. And your open palm about equals one 3-ounce serving of cooked meat, fish, or poultry.

To learn more about how portion sizes have changed in the past 20 years, visit the National Heart, Lung, and Blood Institute’s “Serving Sizes and Portions” web page.