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OpenTrials
Completed

NCT Number: NCT03731273

Compensation for Smaller Portion Sizes and Portion Size Normality

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).

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Key information

Conditions

Portion Size

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Ashleigh Haynes

Liverpool, Merseyside, L69 7ZA, United Kingdom

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

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

Exclusion criteria

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

Treatment and study plan

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.

Primary outcomes

  1. Meal energy intake

    Time frame: Immediate

    Energy intake from the served portion

  2. 'Compensatory' (additional) energy intake

    Time frame: Immediate

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

Sponsors and collaborators

Lead sponsor

University of Liverpool

Other

Collaborators

  • Medical Research Council

Registry information

Official study title

Compensation for Smaller Portion Sizes and Portion Size Normality: Two Laboratory

Important dates

Study start
2016
Primary completion
2017
Study completion
2017
First posted
Nov 6, 2018
Registry last updated
Nov 6, 2018

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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