ASU study: 100-calorie packs make dieters eat more

People who want to lose weight should probably think twice about stocking up on 100-calorie mini-packs. A new study from researchers at Arizona State University and the University of Kentucky shows dieters will actually eat more food and calories if the portions are presented in small sizes and packages.

In a series of experiments, the researchers put 200 calories worth of regular-sized M&Ms into one large plastic bag and 200 calories worth of mini-M&Ms into four smaller plastic bags to simulate mini-packs. Then, two interesting things happened:

1.) Even though the amount of calories was the same, study participants perceived the mini-M&Ms in the small packages to be more like diet food.

2.) At the same time, the participants also believed the four smaller bags contained more calories than the one large bag. This is commonly found where people, in general, see something like six slices of pie as somehow containing more calories than the whole pie itself just because there are more portions.

The conflict between thinking of the mini-packs as both diet food and higher in calories created anxiety and stress for the dieters among the study participants. Dieters tend to have an emotional response to food, anyway, given how much they think about calorie intake and managing their weight. The response was to chow down on multiple mini-packs.

“In addition to the conflict issue, many dieters will also keep on eating once they have already surpassed what they feel is a reasonable amount,” says associate professor Naomi Mandel of the W. P. Carey School of Business at Arizona State University. “It’s referred to as the ‘what the hell’ effect because they feel they’ve already failed their goal, so they keep on binging.”

The research has big-money implications for marketers who sell mini-packs and other reduced-calorie products. Dieters are the main targets for these products. They are also more likely to buy up and consume more of the products if they are packaged in small sizes, so huge profit potential is there.

The study will soon be published in the Journal of Consumer Research. In addition to Mandel, the other researchers were AT&T Distinguished Research Professor of Marketing Stephen Nowlis and Assistant Professor Andrea Morales at the W. P. Carey School of Business at Arizona State University, and Assistant Professor Maura Scott at the Gatton College of Business at the University of Kentucky.