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2.7: Understanding Portion Sizes

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  • Learning Objectives

    • Judge food portion sizes for adequacy.

    Estimating Portion Size

    Have you ever heard the expression, “Your eyes were bigger than your stomach?” This means that you thought you wanted a lot more food than you could actually eat. Amounts of food can be deceiving to the eye, especially if you have nothing to compare them to. It is very easy to heap a pile of food on your plate, particularly if it is a big plate, and not realize that you have just helped yourself to three portions instead of one.

    Part of healthful eating means choosing appropriate amounts of different foods, so knowing more about appropriate portion sizes can be useful. As seen in Figure \(\PageIndex{1}\)1, portion sizes at fast food restaurants have increased over the past several decades and consequently the typical meal contains more calories than it used to. And, it's not just fast food portions that have increased...portion sizes of many foods have gotten larger. In addition, our sedentary lives make it difficult to expend enough calories during normal daily activities. Take the Portion Distortion Quiz at to compare portions from the past to today's portions. The answers to the quiz include examples of the amount of physical activity required to burn off the extra calories provided by today's portions.

    Figure \(\PageIndex{1}\): As food sizes and servings increase it is important to limit the portions of food consumed on a regular basis.

    Dietitians have come up with some good hints to help people tell how large a portion of food they really have. Some suggest using common items such as a deck of cards while others advocate using your hand as a measuring rule. See Table \(\PageIndex{1}\) for some examples.2

    Table \(\PageIndex{1}\): Determining Food Portions
    Amount Object Comparison Hand Comparison Appropriate portion size for:
    ½ cup tennis ball small handful pasta, rice
    1 cup baseball average-sized fist raw or cooked vegetables, whole fruits, beverages
    1 ounce golf ball nuts, cheese
    3 ounces deck of cards average-sized palm of a hand fish, chicken, beef, other meats
    1 Tablespoon thumb salad dressing, nut butters
    1 teaspoon postage stamp thumb tip oils, fats

    Key Takeaways

    • Judging portion sizes can be done using your hand or household objects in comparison.


    1. Portion Sizes - Then and Now. Accessed June 7, 2020.
    2. Serving Size vs Portion Size: Is There a Difference? Accessed June 7, 2020.