Actually, it is the portion size of our meals and not serving sizes of our food that has increased. A portion of food is defined by the USDA as “the amount of food you choose to eat.” A serving of food is defined as “a standard amount used to help give advice about how much to eat or to identify the amount of calories or nutrients in a food.”
Serving sizes for US food guides have been essentially the same since they were introduced in the 1940s. It is just that most Americans either don’t know or don’t care what serving sizes of foods should be. Food labels all have nutritional facts that should include serving size and servings per container. However, the serving size on some labels may be a portion size rather than a standard serving size.
For example, an average portion of meat is 2 or 3 ounces, however one serving is 1 ounce. Therefore, a 36-ounce prime rib special would be 12 servings or 36 portions! This is enough meat for a week or two. Restaurant portion sizes have increased quite obviously in the last 20 to 30 years.
Restaurant plate and glass sizes have also increased to be able to hold it all. Research has shown that a person eats more without realizing it as portion sizes increase. With loaded baked potatoes the size of footballs, half-gallon drinks and cookies the size of Frisbees, it’s easy to see how Americans overeat. Even when healthy foods are eaten, the amounts of those foods are also important. One serving of cooked oatmeal is not whatever fits into your big cereal bowl.
The following guidelines will help in visualizing one standard serving (not portion) for most food guides:
Whole Grain Cereal, Bread, Rice and Pasta
- 1 slice of bread (half of a regular size hamburger bun or bagel)
- 1 cup of dry cereal
- ½ cup of cooked cereal, rice or pasta
Vegetables and Fruits
- 2 cups of raw leafy vegetables
- 1 cup of other vegetables, cooked or raw
- 1 cup of cooked dried beans or peas (one vegetable serving)
- 1 cup of tofu (one vegetable serving)
- 1 cup of vegetable or fruit juice
- 1 medium apple, banana, orange, or other like-sized fruit (about the size of a tennis ball)
- 1 cup of chopped, cooked or canned fruit
- ½ cup dried fruit
Low-Fat Dairy Products
- 1 cup of milk or yogurt
- 1 ½ to 2 ounces of cheese (about the size of a nine‑volt battery)
Fish, Poultry, Lean Meats or Eggs
- 1 ounce of cooked fish, poultry or lean meat for a serving (2 to 3 ounces [about the size of a deck of cards] for a portion)
- 1 egg equals 1 ounce of meat
Nuts, Seeds, Legumes and Plant Oils
- ¼ cup of cooked dry beans or peas (equivalent to 1 ounce of meat)
- ¼ cup of tofu (equivalent to 1 ounce of meat)
- 1 tablespoon of peanut or other nut butters (equivalent to 1 ounce of meat)
- ½ ounce of nuts or seeds (equivalent to 1 ounce of meat)
- 1 teaspoon of plant oils
- 1 teaspoon of nuts or seeds
To be able to estimate these servings, it would be helpful to review the size of household measures, so get out the measuring cups and spoons. Estimate what 1/2 cup of cooked cereal would look like. That way, when you eat that big bowl of oatmeal, you will know that it is really two or three servings. In general, no one portion of food should be bigger than a deck of cards or tennis ball.