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Portion distortion: typical portion sizes selected by young adults.
Jaime Schwartz1, Carol Byrd-Bredbenner
1Rutgers University, New Brunswick, NJ 08901, USA.
Journal of the American Dietetic Association
|September 12, 2006
Summary
Young adults exhibit portion distortion, selecting larger food portions than recommended. This impacts weight management and necessitates nutrition counseling to correct perceptions of appropriate serving sizes.
Area of Science:
- Nutrition science
- Public health
- Behavioral science
Background:
- Rising obesity rates correlate with increased portion sizes in packaged foods, restaurants, and prepared meals.
- Portion distortion, the misperception of appropriate food quantities, may drive increased calorie intake and weight gain.
Purpose of the Study:
- To assess typical portion sizes selected by young adults.
- To compare these selections against reference portion sizes defined by the Nutrition Labeling and Education Act.
- To examine changes in typical portion sizes over time.
Main Methods:
- Young adults (n=177) served themselves typical portions of various foods for breakfast, lunch, and dinner.
- Portion sizes were unobtrusively weighed and compared to established reference quantities.
- A unit score assessed agreement between typical and reference portion sizes, with statistical tests analyzing differences and temporal changes.
Main Results:
- Young adults showed poor agreement between their typical portion selections and reference portion sizes, indicated by low mean unit scores (3.63 for breakfast, 1.89 for lunch/dinner).
- Typical portion sizes selected by participants differed significantly from those reported in a similar study conducted two decades prior.
Conclusions:
- Portion distortion significantly influences the food portions young adults choose.
- This phenomenon can impede weight loss and maintenance efforts.
- Nutrition professionals should develop strategies to address and correct distorted perceptions of appropriate serving sizes for effective counseling.
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