Study shows 'downsizing' options beat calorie warnings in convincing diners to eat less

Studies have shown fast-food calorie postings do little to deter diners from overeating. A better approach may be for restaurants to simply ask consumers if they’d like smaller portions, according to new research by a Freeman School professor in this month’s Health Affairs.

The study, by Janet Schwartz, assistant professor of marketing, found that when servers asked customers whether they’d like to “downsize” starchy side dishes at a Chinese fast-food restaurant as many as a third gladly cut back – saving an average 200 calories each meal.

“Our goal was to test whether the invitation to downsize a meal component would be embraced by consumers and, importantly, whether the approach would be more effective than a purely information-based approach – in this case calorie labeling,” said  Schwartz, the lead study author.

Schwartz and fellow researchers conducted several field experiments at a single Chinese fast-food restaurant. In each case, servers asked customers selecting side dishes, “Would you like to save 200 calories or more by taking a smaller portion?”

In one scenario, customers were offered a 25-cent discount if they took the downsizing offer. In another, menu calorie labels were prominently displayed in front of consumers as they selected their meals and in another calorie labels were removed. In all, anywhere from 14 percent to 33 percent of customers opted to downsize portions. Surprisingly, the 25-cent discount had little impact on downsizing choices and the calorie postings didn’t persuade much either. In fact, significantly more customers —21 percent versus 14 percent — accepted the downsizing offer when calorie information was absent.

Schwartz hopes the study helps restaurants understand that helping diners exercise portion control won’t alienate customers.

“I think the restaurant industry may find this counterintuitive, but it’s an interesting and easy strategy to implement that could help their customers make healthier choices,” Schwartz says.