In a time of rising obesity rates, it was no doubt with good intentions that food manufacturers started packaging their products in single-serve or snack-size portions. But a new study indicates smaller packages can lead to increased consumption.
For the study, published online ahead of print (DOI: 10.1086/589564) in the Journal of Consumer Research, 142 undergraduate students (59 females and 81 males) were asked to watch television, under the guise of rating advertising. They were given either nine, 45 gram bags of crisps, or the same amount of crisps in two, 200gram bags, to eat while watching television. Half of the participants were weighed in front of a mirror and asked if they had any concerns about their size, thus priming them to think about calories.
Overall, 52.1% of the participants (73 out of 140) opened a bag of crisps while watching television, with the average consumption being 49.8 grams.
Those who were weighed prior to watching television were almost twice as likely to start eating from the small bags and, if they did so, they consumed nearly twice as much as the others. Bag size was not shown to have any effect on the amount of crisps eaten by those not made to think about their weight prior to watching television.
"Small package formats may fly under the radar and prevent such internal control, thereby leading to consumption misregulation,” the researchers concluded. “Because they are also willing to pay a price premium for tempting products in small package formats, in particular, consumers with self-regulatory concerns might wind up consuming more rather than less at a higher price."