Portion Size Strategies for Management of Body Weight

The primary aim of this research is to determine the efficacy of two portion-control strategies to achieve sustainable dietary and behavior changes and to promote weight loss and maintenance. A randomized controlled trial will test two approaches to managing portion sizes: one that gives individuals skills and tools to help them make appropriate portion choices, and another that focuses on consumption of pre-portioned foods in order to limit exposure to large portions in the personal food environment. A third group will receive a basic nutritional program to promote weight loss.

The second aim of the research is to determine the effects of the programs on knowledge and consumption of appropriate portions, as assessed by innovative assessment methods and multiple-pass dietary recalls. The third aim is to conduct exploratory analyses of individual factors that may influence the response to the portion-control interventions, such as psychosocial indicators, blood biomarkers, and measures of adherence to the interventions. The expected outcome of the project is that it will lead to the development of specific, evidence-based strategies to help control portion sizes in order to manage weight.

Study Overview

• Status: Completed
• Conditions: Obesity
• Intervention / Treatment: Behavioral: Advice on diet, physical activity, and behavior change; Behavioral: Instruction in food portion size; Other: Provision of pre-portioned foods; Behavioral: Advice on healthy eating for weight loss

• Study Type: Interventional
• Enrollment (Actual): 186
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • University Park, Pennsylvania, United States, 16803
      • Penn State University Laboratory for the Study of Human Ingestive Behavior

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Body mass index of 28 to 45 kg/m squared
• Able to safely engage in physical activity (walking)
• Able to attend regular instructional sessions at University Park, Pennsylvania

Exclusion Criteria:

• have a medical condition diagnosed by a physician that precludes participation
• report symptoms indicative of depression or disordered eating
• report serious food allergies or intolerance
• current or planned participation in a weight-loss program
• pregnant or lactating or planning to become pregnant in the next 18 months

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Portion size instruction; Advice on diet, physical activity, and behavior change. Instruction in food portion size.	Behavioral: Advice on diet, physical activity, and behavior change; Individuals will participate in individual sessions with Registered Dietitians providing basic instruction in principles of weight loss. The program will instruct individuals on the principles of healthy eating and nutrition during calorie restriction. These materials include one module with general information on the importance of limiting portion sizes. The program will also include instruction on physical activity and behavioral strategies for weight loss.; Behavioral: Instruction in food portion size; Individuals assigned to this program will participate in individual instructional sessions with specialized materials and tools that address food selection and choosing appropriate portion sizes of various foods.
Experimental: Pre-portioned foods; Advice on diet, physical activity, and behavior change. Provision of pre-portioned foods.	Behavioral: Advice on diet, physical activity, and behavior change; Individuals will participate in individual sessions with Registered Dietitians providing basic instruction in principles of weight loss. The program will instruct individuals on the principles of healthy eating and nutrition during calorie restriction. These materials include one module with general information on the importance of limiting portion sizes. The program will also include instruction on physical activity and behavioral strategies for weight loss.; Other: Provision of pre-portioned foods; Individuals assigned to this program will be provided with commercially available pre-portioned foods and will be taught effective ways to incorporate them into their daily diet.
Active Comparator: Comparison; Advice on diet, physical activity, and behavior change. Advice on healthy eating for weight loss.	Behavioral: Advice on diet, physical activity, and behavior change; Individuals will participate in individual sessions with Registered Dietitians providing basic instruction in principles of weight loss. The program will instruct individuals on the principles of healthy eating and nutrition during calorie restriction. These materials include one module with general information on the importance of limiting portion sizes. The program will also include instruction on physical activity and behavioral strategies for weight loss.; Behavioral: Advice on healthy eating for weight loss; Individuals assigned to this program will participate in individual instructional sessions that address principles of healthy eating while on a calorie-restricted diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in body weight	Body weight will be measured at multiple time points during the 12-month trial; the main outcome will be the weight trajectory across this time	Months 0 to 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in portion size selection, perception, and knowledge	Computerized assessment of various foods (for self-selected portion sizes, estimation of calorie content, and satiety value) and general knowledge about portion size	Months 0, 3, 6, & 12
Change in portion size consumption	Portion sizes consumed in various food categories as assessed by diet recalls and diet records	Months 0, 3, 6, & 12
Change in blood biomarkers	Fasting lipids, glucose, insulin, and calculated insulin resistance	Months 0, 3, 6, & 12
Change in waist circumference		Months 0, 3, 6, & 12
Change in blood pressure		Months 0, 3, 6, & 12
Change in dietary intakes	Energy intake, nutrient intakes, dietary energy density, food group intakes, and diet quality from three days of 24-hour diet recalls	Months 0, 3, 6, 9, & 12
Change in step counts	Daily step counts from pedometers	Months 0, 3, 6, 9, & 12
Change in attitudes and behaviors related to food and eating	Self-reported eating attitudes and behaviors on multiple questionnaires	Months 0, 1, 3, 6, & 12
Change in psychosocial characteristics	Questionnaires measuring psychosocial characteristics including impulsivity, variety-seeking, and self-efficacy	Months 0, 3, 6, & 12
Intervention adherence	Number of sessions attended, number of diet and activity records completed, and frequency of using intervention strategies during the entire trial	Month 12

Collaborators and Investigators

• Sponsor: Penn State University
• Collaborators: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
• Investigators: Principal Investigator: Barbara J. Rolls, PhD, Penn State University

Publications and helpful links

General Publications

• Roe LS, Rolls BJ. Which strategies to manage problem foods were related to weight loss in a randomized clinical trial? Appetite. 2020 Aug 1;151:104687. doi: 10.1016/j.appet.2020.104687. Epub 2020 Mar 29.
• James BL, Loken E, Roe LS, Rolls BJ. The Weight-Related Eating Questionnaire offers a concise alternative to the Three-Factor Eating Questionnaire for measuring eating behaviors related to weight loss. Appetite. 2017 Sep 1;116:108-114. doi: 10.1016/j.appet.2017.04.023. Epub 2017 Apr 22.

Study record dates

Study Major Dates

• Study Start: July 1, 2012
• Primary Completion (Actual): March 1, 2015
• Study Completion (Actual): March 1, 2015

Study Registration Dates

• First Submitted: November 15, 2011
• First Submitted That Met QC Criteria: November 17, 2011
• First Posted (Estimate): November 18, 2011

Study Record Updates

• Last Update Posted (Estimate): May 15, 2015
• Last Update Submitted That Met QC Criteria: May 14, 2015
• Last Verified: May 1, 2015

More Information

Terms related to this study

• Other Study ID Numbers: PortionSize101; R01DK059853 (U.S. NIH Grant/Contract)