Portion Size and To-go Container on Dinner Intake

The Influence of the Provision of a To-go Container on the Portion Size Effect in Women

This study investigated whether the provision of a to-go container influenced the portion size effect at a meal. Following a screening visit, women came to the lab once a week for 4 weeks to eat a meal of multiple foods. At each visit, the portion size of the meal was varied in a counterbalanced order. Prior to their first meal, women were randomly assigned to one of two groups: a group that would have their leftovers packaged to go (to-go group) and a group that did not have leftovers packaged (control group). Women were instructed to eat ad libitum at the meals. They also answered questions about hunger and fullness as well as food characteristics before and after each meal. Following the final meal, subjects completed a series of questionnaires assessing subject characteristics as well as food characteristics. It was hypothesized that the effect of portion size on intake would be attenuated in subjects who received a to-go container with the meal. In addition, we aimed to identify any subject characteristics that moderated or exacerbated the portion size effect. It was also of interest to determine whether the portion size effect on individual foods were influenced by food characteristics such as perceived value.

Study Overview

• Status: Completed
• Conditions: Obesity; Eating Behavior
• Intervention / Treatment: Behavioral: To-Go container; Other: Control

• Study Type: Interventional
• Enrollment (Actual): 58
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Regularly eats 3 meals/day
• Willing to avoid alcohol the day before and during test days
• Likes foods offered at test meals
• Body mass index 18 - 36 (kg/m*m)

Exclusion Criteria:

• Smokes
• Athlete in training
• Pregnant or breastfeeding
• Taking medication that may affect appetite or food intake
• Food allergies or dietary restrictions
• Currently have or recently been diagnosed with disease or disorder known to affect appetite

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 100% portion size; 100% portion sizes of all foods served (baseline). To-go container and controls received this meal.	Behavioral: To-Go container; Subjects were provided a to-go container in which leftover foods would be packaged; Other: Control; Subjects were not provided a to-go container with the meal
Experimental: 125% portion size; 125% of baseline portions served. To-go container and controls received this meal.	Behavioral: To-Go container; Subjects were provided a to-go container in which leftover foods would be packaged; Other: Control; Subjects were not provided a to-go container with the meal
Experimental: 150% portion size; 150% of baseline portions served. To-go container and controls received this meal.	Behavioral: To-Go container; Subjects were provided a to-go container in which leftover foods would be packaged; Other: Control; Subjects were not provided a to-go container with the meal
Experimental: 175% portion size; 175% of baseline portions served. To-go container and controls received this meal.	Behavioral: To-Go container; Subjects were provided a to-go container in which leftover foods would be packaged; Other: Control; Subjects were not provided a to-go container with the meal

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the weight of food consumed	Change in the weight of food consumed (in grams) across experimental conditions and intervention groups.	Weeks 1, 2, 3, and 4
Change in energy intake	Change in energy intake (in kcal) across experimental conditions and intervention groups.	Weeks 1, 2, 3, and 4

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in energy density consumed	Change in food energy density consumed (in kcal/g) across experimental conditions and intervention groups.	Weeks 1, 2, 3, and 4
Change in intake of individual foods	Change in both the weight (g) and energy (kcal) consumed of individual foods served at the meal across experimental conditions and intervention groups.	Weeks 1, 2, 3, and 4
Changes in post-meal measures of satiety	Changes in post-meal measures of satiety across experimental conditions and intervention groups using 100-mm visual analog scales.	Weeks 1, 2, 3, and 4
Changes in post-meal ratings of meal characteristics	Changes in post-meal ratings of meal characteristics across experimental conditions and between subject groups using 100-mm visual analog scales.	Weeks 1, 2, 3, and 4
Changes in ratings of food properties	Changes in post-meal ratings of food properties across experimental conditions and subject groups using 100-mm visual analog scales.	Weeks 1, 2, 3, and 4

Collaborators and Investigators

• Sponsor: Penn State University
• Collaborators: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); United States Department of Agriculture (USDA); Jenny Craig, Inc.
• Investigators: Principal Investigator: Barbara J. Rolls, PhD, The Pennsylvania State University

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2016
• Primary Completion (Actual): December 1, 2017
• Study Completion (Actual): December 1, 2017

Study Registration Dates

• First Submitted: April 3, 2018
• First Submitted That Met QC Criteria: April 10, 2018
• First Posted (Actual): April 18, 2018

Study Record Updates

• Last Update Posted (Actual): April 18, 2018
• Last Update Submitted That Met QC Criteria: April 10, 2018
• Last Verified: April 1, 2018

More Information

Terms related to this study

• Keywords: energy intake; food choice; food intake; portion size
• Other Study ID Numbers: PortionSize105; R01DK059853 (U.S. NIH Grant/Contract); NIFA Grant 2011-67001-30117 (Other Grant/Funding Number: United States Department of Agriculture)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No