Portion‐size preference as a function of individuals' body mass index

Abstract

SummaryObjectiveLarge portions of food are often blamed for rising rates of obesity. We tested the possibility that people who are heavier may tend to select or prefer larger portions than do people who are lighter.MethodsParticipants (total N = 798) were asked to choose between a small and larger portion of pasta for a hypothetical meal (Studies 1, 2 and 4), to indicate their ideal portion from a range of portion‐size options (Study 2), or to select their preferred portion size from each of 28 portion pairs (Study 3).ResultsAcross all studies, there were no significant differences between heavier and lighter participants in their portion‐size selection (effect sizes ranged from d = −0.06 to 0.33). The pattern was the same regardless of whether we grouped participants as having a body mass index (BMI) <25 vs. ≥25, as having a BMI of <30 vs. ≥30, or treated BMI as a continuous predictor.ConclusionsGiven the lack of association between BMI and portion‐size preference, we suggest that factors other than portion size, such as differences in meal frequency, food type, plate clearing or compensation at subsequent meals, may need to be considered in order to explain the increasing prevalence of obesity.

Gender, Age, Hunger, and Body Mass Index as Factors Influencing Portion Size Estimation and Ideal Portion Sizes

“…Despite the estimation raising with increasing BMI, BMI did not affect normal portion sizes statistically significantly. Previous studies show contradictory results ( Dodd et al, 1976 ; Burger et al, 2007 ; Brunstrom et al, 2008 ; Lewis et al, 2015 ; Reily et al, 2016 ; Embling et al, 2021 ). Likely, the presentation style and type depicted foods play a role in the outcomes as the study from Burger et al (2007) reported a positive relationship between BMI and some of the foods tested (peanuts, M&M candies, cereals, jam, and soda), but also some foods with a negative relationship (margarine and apple sauce) and some with no differences (rice, chips, peanut butter, macaroni and cheese, and water).…”

“…However, other reports with a similar design found no difference as a function of BMI ( Brunstrom et al, 2008 ; Embling et al, 2021 ). In studies allowing the choice between fixed portion sizes, some indicated that participants with obesity order larger portions than non-obese ( Dodd et al, 1976 ) which was not confirmed by other reports ( Reily et al, 2016 ). Thus, the issue of the relation between BMI and portion size is controversial and remains unresolved.…”

“…Conscious as well as subconscious factors or mechanisms responsible for influencing the Portion-Size-Effect include unit bias ( Geier et al, 2006 ), expected satiety ( Brunstrom and Rogers, 2009 ), energy compensation ( Benton, 2015 ), bite-size ( Almiron-Roig et al, 2018 ), visual stimuli ( Marchiori et al, 2011 ; Penaforte et al, 2014 ), financial aspects ( Benton, 2015 ; Steenhuis and Poelman, 2017 ), and portion norms ( Lewis et al, 2015 ). In the context of Portion-Size-Effect, the subconscious mechanisms are reflected in the lack of differentiation when people eat from a large portion versus a small portion, despite consuming more ( Levitsky and Youn, 2004 ) even after being informed about the difference in portions sizes ( Spanos et al, 2015 ; Reily et al, 2016 ). Furthermore, consumption of bigger portion sizes and lack of restriction was observed even when the portions are served consistently over multiple subsequent meals ( Rolls et al, 2007 ).…”