Your Co-worker Might Have More Food Influence Than You Think

People may change their behavior to cement the relationship with someone in their social circle

A new study by researchers at the University of Massachusetts Amherst, has found that when co-workers are eating together, individuals are more likely to select foods that are as healthy—or unhealthy—as the food selections on their fellow employees’ trays. “We found that individuals tend to mirror the food choices of others in their social circles, which may explain one way obesity spreads through social networks,” says Douglas Levy, an investigator at the Mongan Institute Health Policy Research Center at Massachusetts General Hospital (MGH) and first author of the new paper, which was published online in Nature Human Behaviour. The investigators discovered that individuals’ eating patterns can be shaped even by casual acquaintances, evidence that corroborates several multi-decade observational studies showing the influence of people’s social ties on weight gain, alcohol consumption and eating behavior. The new study examined the cumulative social influence of food choices among approximately 6,000 MGH employees of diverse ages and socioeconomic status as they ate at the hospital system’s seven cafeterias over two years. The healthfulness of employees’ food purchases was determined using the hospital cafeterias’ “traffic light” labeling system designating all food and beverages as green (healthy), yellow (less healthy) or red (unhealthy).

MGH employees may use their ID cards to pay at the hospitals’ cafeterias, which allowed the researchers to collect data on individuals’ specific food purchases, and when and where they purchased the food. Based on cross-sectional and longitudinal assessments of three million encounters between pairs of employees making cafeteria purchases together, the researchers found that food purchases by people who were connected to each other were consistently more alike than they were different. Why do people who are socially connected choose similar foods? Peer pressure is one explanation. “People may change their behavior to cement the relationship with someone in their social circle,” says Levy. Co-workers may also implicitly or explicitly give each other license to choose unhealthy foods or exert pressure to make a healthier choice. As we emerge from the pandemic and transition back to in-person work, we have an opportunity to eat together in a more healthful way than we did before, according to the results of the study.