by Black B

Related Media: Food Choices for Weight Loss

IMAGE Most people consume far more calories than they realize. The culprit? A warped sense of portion size.

Did you know that a portion size is different than a serving size? If not, you are not alone. Since the mid-1980's, portion sizes have grown. This means Americans eat more calories than we need without realizing it. One way to bring yourself back to a healthy weight is to manage your calorie intake. The US Department of Agriculture recommends that you enjoy your food, but eat less. By doing so, you will not have to completely eliminate foods you like. You will just have to control portion sizes.

Serving Sizes Essential to Good Nutrition

Experts say that understanding the concept of standard serving sizes is essential to good nutrition. Standardized serving sizes help consumers, health professionals, and food manufacturers find a common language for the sake of communication.

Although serving sizes are standardized, individual portion sizes will vary because people have different caloric requirements. Portion size also depends on a person's specific weight management goals and health needs. For example, pregnant and breastfeeding women may require larger portions of food than do women who are not pregnant or nursing.

Nutritional Needs Vary

Portion sizes and overall dietary requirements depend on several factors, including activity level. For example, an inactive person may only need ¾-1 cup of cereal in the morning, which is the usual serving size of most varieties. But someone who runs several miles a day or who engages in other forms of aerobic exercise may need 2-3 standard serving sizes.

To help determine a standard serving size, measure out what is listed on the "Nutrition Facts" food label.

Ways to Estimate Portion Sizes

What is a portion size? Try following these models to approximate portion sizes:

  • A small bar of soap = one serving (3 ounces) of meat, poultry, or fish
  • A closed fist = one serving (1 cup or 8 ounces) of pasta
  • Your thumb = one serving (1 1/2 ounces) of cheese
  • A tennis ball = one serving (1 ounce) of cereal
  • When at home:
    • Take time to eyeball the serving sizes of your favorite foods using some of the models listed above.
    • Measure out single servings onto your plates and bowls, and remember what they look like. Figure out how many servings should make up your personal portion, depending on whether you need to lose, gain, or maintain weight.
    • Avoid serving food family style. Serve up plates with appropriate portions in the kitchen, and do not go back for seconds.
    • Consider using smaller plates, bowls, or glasses.
    • Never eat out of the bag or carton.
    • If you feel hungry, go ahead and eat a healthy snack. It may help you eat smaller portions at meal time.
  • When in restaurants:
    • Ask for half or smaller portions.
    • Eyeball your appropriate portion, set the rest aside, and ask for a take out container before you eat.
    • If you order dessert, share it, or choose a healthier option like fruit.

Seek Dietary Guidance

If you are unsure about your personal nutrition requirements, go to the Choose My Plate website to get eating recommendations based on factors like your age, sex, and activity level. For an even more individualized plan and for motivation, seek the advice of a registered dietitian. These professionals can create individual menus and food plans that are suited to your specific weight management and overall health goals.


Choose My Plate—US Department of Agriculture 

Eat Right—Academy of Nutrition and Dietetics 


Dietitians of Canada 

Health Canada 


6 tips for dining out without blowing your nutrition plan. Eat Right—Academy of Nutrition and Dietetics website. Available at: Updated October 30, 2015. Accessed February 3, 2017.

Diets for weight loss. EBSCO DynaMed Plus website. Available at: . Updated January 30, 2017. Accessed February 3, 2017.

Dietary guidelines for Americans 2015-2020. Office of Disease Prevention and Health Promotion website. Available at: Updated December 2015. Accessed February 3, 2017.

Estimating portion sizes. University of Arkansas Division of Agriculture website. Available at: Accessed February 3, 2017.

How to avoid portion size pitfalls to help manage your diet. Centers for Disease Control and Prevention website. Available at: Updated July 6, 2016. Accessed February 3, 2017.

Kausman R. Tips for long-term weight management. Aust Fam Physician. 2000;29(4):310-313.

Kesman RL, Ebbert JO, Harris KI, Schroeder DR. Portion control for the treatment of obesity in the primary care setting. BMC Res Notes. 2011;4:346.

Sacks FM, Bray GA, Carey VJ, et al. Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates. N Engl J Med. 2009;360(9):859-873.

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