MedPath

Enhanced Broccoli Consumption After a Liking Norm and Vegetable Variety Message: Effects After a 24 Hour Delay.

Not Applicable
Completed
Conditions
Eating Behaviour
Registration Number
NCT02618174
Lead Sponsor
University of Birmingham
Brief Summary

Encouraging individuals to eat vegetables is difficult. However, recent evidence suggests that using social-based information might help. For instance, it has been shown that if people think that others are eating lots of fruit and vegetables, that they will consume more of these foods to match the 'norm'. The purpose of this study was to determine whether a liking social norm (information about how much others like vegetables) would be effective at encouraging people to eat more vegetables and to examine whether these effects are sustained beyond initial exposure (i.e. whether the effect of the norm persists on food selection 24 hours alter).

Detailed Description

Using a 2 x 5 x 2 experimental design we investigated the effects of exposure to various messages on later food intake and whether any effects were sustained 24 hours after exposure in both low and high consumers of vegetables. There were three factors of delay (immediate food selection versus food selection 24 hours after exposure), message type (liking norm, descriptive norm, health message, food-based control, and neutral control message) and habitual consumption (low versus high). The buffet consisted of three raw vegetables, three energy-dense foods and two dips.

In this study the investigators hypothesised that a liking norm would increase the consumption of vegetables (compared to a neutral control condition) and that the effect would persist on vegetable consumption 24 hours after intital exposure to the liking norm.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
400
Inclusion Criteria
  • Healthy volunteers
  • Sufficiently fluent in English
Exclusion Criteria
  • Smokers
  • Diabetes
  • Food allergies
  • Past / present depression or anxiety
  • Past / present eating disorder.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
Grams of vegetables consumed8 months
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

University of Birmingham

🇬🇧

Birmingham, West Midlands, United Kingdom

University of Birmingham
🇬🇧Birmingham, West Midlands, United Kingdom

MedPath

Empowering clinical research with data-driven insights and AI-powered tools.

© 2025 MedPath, Inc. All rights reserved.