Researchers at George Mason University have identified key social and environmental factors that shape how much college students eat. In a four-week study using a mobile app and daily surveys, students tended to consume more calories when eating with multiple companions or in formal dining settings, even as many reported that they believed they were eating less in those situations.
The term "freshman 15" is often used to describe the common perception that first-year college students gain about 15 pounds during their first year on campus. While the exact amount of weight gain varies across studies, researchers say the phrase reflects broader concerns about how college life can disrupt healthy eating and activity patterns.
A recent longitudinal study led by Y. Alicia Hong, a professor in the Department of Health Administration and Policy at George Mason University, examined how social and environmental contexts influence college students’ eating behaviors. Hong, whose work focuses on mobile and wearable technology in health research, collaborated with an interdisciplinary team to analyze how campus settings, social company, mood and stress relate to how much students eat.
Over four weeks in spring 2022, 41 George Mason University students aged 18 to 25 used the commercial Nutritionix mobile app to log everything they ate or drank and completed a brief daily online survey documenting where they ate, whom they ate with, and their mood and stress levels. In total, 3,168 eating occasions were recorded.
App data showed that students consumed more calories when eating with two or more companions and when dining in formal settings such as dining halls or sit-down restaurants, compared with eating alone or at home or in a dorm. In contrast, calorie intake tended to be lower when eating at home and, in many cases, when eating alone.
The authors reported that social and environmental conditions were important determinants of eating behavior in this sample of young adults. They found that the number of eating companions and the type of eating location were strongly associated with total calorie intake, after accounting for other factors such as gender, body mass index, mood, stress and type of meal.
The study also identified discrepancies between students’ self-perceptions and their objective intake. When students ate with two or more companions or in formal dining locations, they were more likely to report in surveys that they had eaten less than usual, even though the app data showed that they had consumed more calories on average in those settings. The researchers interpret this as evidence that students may underestimate their intake in social and formal dining contexts.
Gender differences further complicated the picture. According to the study, male students consumed significantly more calories when eating with two or more companions and in formal dining settings, suggesting a strong social influence on their intake. Female students, by contrast, often showed higher calorie intake in formal dining environments but were less likely to report that they had eaten more than usual, pointing to a mismatch between actual and perceived consumption.
The paper also noted that mood and stress were associated with eating patterns. Happy moods were linked to higher calorie intake overall, particularly among male students, while high stress did not consistently increase calories consumed but did influence how students reported their eating, especially among women. Body mass index was another factor associated with variations in intake, underscoring the complexity of eating behaviors in this age group.
The research team included Larry Cheskin, a professor in the Department of Nutrition and Food Studies; Hong Xue, a professor in Health Administration and Policy; and Jo-Vivian Yu, a graduate of the Master of Science in Health Informatics program. Their article, titled "The dynamics of eating behaviors and eating environment in college students: discrepancies between app-tracked dietary intake and self-perceived food consumption," was published in the journal mHealth in 2025.
In discussing their findings, the authors argue that college students’ eating behaviors are shaped by individual, interpersonal and environmental factors acting together. They suggest that nutrition interventions for young adults should account for social context and location, and should consider using digital tools such as dietary apps to capture objective intake. They also highlight the need to address gaps between perceived and actual consumption when designing programs to promote healthier eating on college campuses.
The study was supported by a pilot grant from the George Mason University College of Public Health, with Hong serving as principal investigator.
