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Unpublished Paper
How Much Serving Size Affects Consumption : Catch-22
  • Natalina Zlatevska, Bond University
  • Chris Dubelaar, Bond University
  • Stephen S Holden, Bond University
The effect of serving-size on consumption is well-established: the larger the serve, the greater the amount consumed. But what is the size of the effect, what are the processes driving the effect, and what are the conditions that facilitate vs. inhibit the effect? The present research uses a meta-analysis of 67 studies to quantify the effect of serving-size on amount consumed and to test two competing explanations of why the effect occurs. One view is that the serving-size is mediated by a perceptual effect, the other that it is mediated by a consumption norm. The meta analysis demonstrates that when serving-sizes double, consumption can be expected to increase by 22%; the effect is consistent with a perceptual effect rather than a consumption norm; the effect is stronger among adults than children, and stronger when attention is not on the food is ‘incidental’ rather than ‘focal’ to the situation.
  • serving-size,
  • portion-size,
  • food consumption,
  • consumption norm,
  • unit bias,
  • perceptual effect,
  • psychophysical effect,
  • meta-analysis
Publication Date
Working Paper (feedback is welcome)
Citation Information
Natalina Zlatevska, Chris Dubelaar and Stephen S Holden. "How Much Serving Size Affects Consumption : Catch-22" (2012)
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