Plate size and food consumption: A pre-registered experimental study in a general population sample

Daina Kosite, Laura Konig, Katie J De-loyde, Ilse Lee, Emily Pechey, Natasha Clarke, Olivia M Maynard, Richard W Morris, Marcus R. Munafò, Theresa M Marteau, Paul Fletcher, Gareth J Hollands

Research output: Contribution to journalArticle (Academic Journal)

3 Citations (Scopus)
138 Downloads (Pure)

Abstract

Background
There is considerable uncertainty regarding the impact of tableware size on food consumption. Most existing studies have used small and unrepresentative samples and have not followed recommended procedures for randomised controlled trials, leading to increased risk of bias. In the first pre-registered study to date, we examined the impact on consumption of using larger versus smaller plates for self-served food. We also assessed impact on the underlying meal micro-structure, such as number of servings and eating rate, which has not previously been studied.

Methods
The setting was a purpose-built naturalistic eating behaviour laboratory. A general population sample of 134 adult participants (aged 18–61 years) was randomly allocated to one of two groups varying in the size of plate used for self-serving lunch: large or small. The primary outcome was amount of food energy (kcal) consumed during a meal. Additionally, we assessed impact on meal micro-structure, and examined potential modifying effects of executive function, socio-economic position, and sensitivity to perceptual cues.

Results
There was no clear evidence of a difference in consumption between the two groups: Cohen’s d = 0.07 (95% CI [− 0.27, 0.41]), with participants in the large plate group consuming on average 19.2 (95% CI [− 76.5, 115.0]) more calories (3%) compared to the small plate group (large: mean (SD) = 644.1 (265.0) kcal, versus small: 624.9 (292.3) kcal). The difference between the groups was not modified by individual characteristics. There was no evidence of impact on meal micro-structure, with the exception of more food being left on the plate when larger plates were used.

Conclusions
This study suggests that previous meta-analyses of a low-quality body of evidence may have considerably overestimated the effects of plate size on consumption. However, the possibility of a clinically significant effect – in either direction – cannot be excluded. Well-conducted trials of tableware size in real-world field settings are now needed to determine whether changing the size of tableware has potential to contribute to efforts to reduce consumption at population-level.
Original languageEnglish
Article number75 (2019)
Number of pages9
JournalInternational Journal of Behavioral Nutrition and Physical Activity
Volume16
DOIs
Publication statusPublished - 28 Aug 2019

Structured keywords

  • Physical and Mental Health
  • Nutrition and Behaviour

Keywords

  • Plate size
  • Food consumption
  • Choice architecture
  • Nudging
  • Physical micro-environment

Fingerprint Dive into the research topics of 'Plate size and food consumption: A pre-registered experimental study in a general population sample'. Together they form a unique fingerprint.

  • Cite this