Piece‐Meal: Food is more filling when cut into pieces

We wished to examine whether cutting food into several pieces led to its being rated as more filling. Satiety is driven by psychological, as well as physiological, factors (Wansink 2007; Redden and Galak 2013). If people think they ate a more substantial meal, they feel fuller (Wansink et al. 2010). Perceived quantity can influence psychological satiety (Redden and Galak 2013; Wansink 2007; Tal and Wansink 2014). Here, we wish to examine whether increasing the number of units in a meal by cutting a bagel into pieces increases reported satiety. Participants (N = 43) completed the study for credit in a behavioral lab. They were randomly assigned to one of three groups. The study was run in the afternoon. Groups alternated every half hour. All groups were served a mini‐bagel (approximately 42.5 grams) with cream cheese. One group received the bagel whole. The other two groups received the bagel cut into four pieces. For one of those group, the bagel pieces were kept together. For the other, the pieces were spread apart. Participants were instructed to eat the bagel in its entirety. They then reported on fullness on measures of hunger, fullness, and satiation, all reported on 9‐point likert scales, added up to a summary satiety score. Measures were taken pre and post consumption, allowing calculation of increase/decrease in satiation as our dependent measure. A follow‐up replication was conducted with a larger sample (N = 72). In the replication study, we examined moderation by liking for bagels, measured on a 9‐point likert scale. Satiety increased the most for the pieces‐together condition (4.77). Whole bagel participants had the second highest increase in satiety (3.75), while those with the pieces apart reported the lowest increase in satiety (2.18). The effect was significant at a .04: F(2, 41) = 3.26. In the replication study, the effect of condition was significant at a .02 level: F (2, 64) = 4.21. Those in the 4‐pieces condition reported a higher increase in satiety (3.29) relative to eating the bagel whole (2.63). Once again, bagel cut into four spread pieces led to the lowest increases in satiety (1.72). There was also a marginally significant interaction of liking and condition: F(2, 64) = 3.02, p = .056, with those expressing greater liking displaying weaker effects. Food is perceived as more filling when divided into several pieces. Spreading the food apart mitigates the effect. This is likely because food volume appears lower when spread out, creating an overall appearance of a smaller serving. This provides evidence that it is the number of units, rather than the filling of the plate (Wadhera et al. 2012), that leads to increased satiety. Cutting food to pieces can help consumers feel fuller with similar amounts of food. Knowledge of this effect can thus help reduce overeating and consequent obesity.