Compensation for Smaller Portion Sizes and Portion Size Normality

NCT03731273 | Completed

• 1 other identifier: Portion size normality
• Study Type: interventional
• Target: 90
• Locations: 1 country
• Sites: 1

Brief Summary

Reducing food portion size is a potential strategy to reduce energy intake. However it is unclear at what point consumers compensate for reductions in portion size by increasing energy intake from other items. The investigators tested the hypothesis that reductions to food portion size will only result in significant compensatory eating when the reduced portion size is no longer visually perceived as 'normal'. In two within-subjects experiments, participants (Study 1: N = 45, M BMI = 26.9; Study 2: N = 37, M BMI = 26.9; 51% female) were served different sized portions of a lunchtime meal on three occasions: a 'large-normal', a 'small-normal', and a 'smaller than normal' portion. Both the reduction from 'large-normal' to 'small-normal' and from 'small-normal' to 'smaller than normal' portions represented the same change in food volume and energy content (84g, 77kcal Study 1; 98g, 117kcal Study 2). Participants were able to serve themselves additional helpings of the same food (Study 1), or dessert items (Study 2).

Conditions

Portion Size

Outcome Measures

Primary Outcomes (2)

• Meal energy intake

  Energy intake from the served portion

  Immediate

• 'Compensatory' (additional) energy intake

  Energy intake from additional food provided for consumption after the portion-manipulated meal

  Immediate

Interventions

portion size BEHAVIORAL

Smaller than normal portion size - the intervention is the meal size perceived as 'smaller than normal' that participants are provided with during a lunchtime session in the laboratory. 'Small-normal' portion size - the intervention is the meal size perceived as 'small normal' that participants are provided with during a lunchtime session in the laboratory. 'Large normal' portion size - the intervention is the meal size perceived as 'large normal' that participants are provided with during a lunchtime session in the laboratory.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• general liking and willingness to consume the test foods in each study

You may not qualify if:

• food allergies, intolerances or specific dietary requirements (including being vegetarian or vegan)
• a history of eating disorders;

Sponsors & Collaborators

• University of Liverpool: lead
• Medical Research Council: collaborator

Study Sites (1)

Ashleigh Haynes

Liverpool, Merseyside, L69 7ZA, United Kingdom

Location

MeSH Terms

Interventions

Portion Size

Intervention Hierarchy (Ancestors)

Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Lecturer

Study Record Dates

• First Submitted: November 2, 2018
• First Posted: November 6, 2018
• Study Start: October 4, 2016
• Primary Completion: July 25, 2017
• Study Completion: July 25, 2017
• Last Updated: November 6, 2018

Record last verified: 2018-11

Data Sharing

• IPD Sharing: Will share

Locations

GB (1)