Large company may equate to large appetite. So says a new report on how dining company can influence one’s choices at the table. The work builds on previous evidence for weight similarity among friends and indicates that dining with an overweight companion may not only lead one to eat more but eat more unhealthful food also.

The new report, published in the aptly named journal Appetite, found that college undergraduates who were offered pasta and salad while dining near a normal weight female diner would eat more pasta when the woman was wearing a fat suit. The suit was designed to give the appearance of an extra 50 pounds of body weight and eight additional body mass index points.

“We’ve long known that what a person orders can influence what you order,” Brian Wansink, director of the Cornell University Food and Brand Lab and study co-author, said in an interview. “We haven’t known as fully how the size of the person who you might be with, how they influence us.”

Wansink and colleagues followed 82 Cornell University students while they were provided a pasta and salad buffet lunch and accompanied by an actress from upstate New York who either wore the fat suit or dined normally. The actress portrayed four different personas: slim and healthful eating; fat suit and healthful eating; slim and unhealthful eating; and fat suit and unhealthful eating. Healthful eating meant that the actress consumed much more salad than pasta; unhealthful meant more pasta than salad.

The actress was always in the dining room before the groups of students. She was instructed in each trial to draw attention to herself by asking whether she needed separate plates for pasta and salad, respectively. She then took her food, sat down, and pretended to eat it. After each lunch, the group of students completed questionnaires.

The amount of food on the actress’s plates had no effect on the students’ behavior. In contrast, her apparent weight did. While slim and eating unhealthful, the actress’s behavior had little influence on the behavior of the students. However, when the actress wore the fat suit and was in front of or next to the students, the students took more food.

To resist these subtle influences, Wansink says, “It’s really important to commit to what and how much food you want to eat before you get to the restaurant. … It takes very little to throw us off our game.”