Social Norms Influence Food Choices, Meta-Analysis of Eating Habits Reveal

People use food to shape their social identity and diners feed off information provided to them by one another when making food choices, according to a new meta-analysis of 15 scientific studies.

Lead investigator Eric Robinson from the University of Liverpool and his colleagues conducted a systematic review of the studies, which were published in 11 different journals. Each of the studies in the analysis examined whether or not providing information about other peoples' eating habits influenced peoples' food intake or food choices. Eight of the studies examined how information about food intake norms influenced food consumed by participants, and seven others reported on the effects of how food choice norms influence how people decide what to eat.

By synthesizing the results of all these studies, Robinson and his team found consistent data revealing that when people were given information on when their dining companions were making high-calorie or low-calorie dining choices, it significantly increased the likelihood that participants made similar choices.

The meta-analysis also revealed that social norms influence how much food is eaten and that if it was suggested that people eat a larger portion of food then they typically would.

"It appears that in some contexts, conforming to informational eating norms may be a way of reinforcing identity to a social group, which is in line with social identity theory," Robinson said in a statement. "By this social identity account, if a person's sense of self is strongly guided by their identity as a member of their local community and that community is perceived to eat healthily, then that person would be hypothesized to eat healthily in order to maintain a consistent sense of social identity."

Additionally, the analysis revealed that the social mechanisms that influence what we decide to eat and drink are in place even when people are alone.

"Norms influence behavior by altering the extent to which an individual perceives the behavior in question to be beneficial to them. Human behavior can be guided by a perceived group norm, even when people have little or no motivation to please other people," Robinson said. "Given that in some studies the participants did not believe that their behavior was influenced by the informational eating norms, it seems that participants may not have been consciously considering the norm information when making food choices.

"The evidence reviewed here is consistent with the idea that eating behaviors can be transmitted socially," Robinson said. "Taking these points into consideration, the findings of the present review may have implications for the development of more effective public health campaigns to promote 'healthy eating.' Policies or messages that normalize healthy eating habits or reduce the prevalence of beliefs that lots of people eat unhealthily may have beneficial effects on public health."

Robinson and his colleagues published their work in the Journal of the Academy of Nutrition and Dietetics.