Context of college weight gain: Researchers unpack situational contributors to “freshman 15”

A new behavioral study underscores that US college students’ campus environment lends itself to habits that increase their food intake and subsequent weight gain. They are also largely unaware of their eating habits, as the analysis reveals that their self-perceptions of food consumption generally do not align with their logged caloric intake.

The study authors were particularly interested in the “freshman 15,” a phenomenon which refers to a time at the start of college when many students gain around 15 pounds. In particular, factors related to gender and emotion significantly contributed to the complexities of dietary behaviors, they highlight.

Over the course of four weeks, US college students participating in the study used a mobile app to self-record information about their daily eating behaviors, environment, mood, and stress levels.

App-logged responses indicated participants eat more calories when in groups of two or more and in locations such as dining halls or restaurants. Conversely, their food intake was lower when they were alone or at home.

“Social and environmental factors are key determinants of eating behavior. College students are affected by the eating environment, especially where they eat and who they eat with,” says Alicia Hong, study lead, who studies mobile and wearable technologies and professor in the Department of Health Administration and Policy.

“College students’ eating behaviors are complex, with individual, interpersonal, and environmental factors interacting to influence dietary intake. This research underscores the importance of context in dietary intervention and incorporating digital tools for dietary assessment.”

Outlining unhealthy diet behaviors

US data from the most recent National College Health Assessment reveals that 15% of college students eat recommended daily servings of fruits and vegetables.

During the COVID-19 pandemic, many college students adopted unhealthy dietary behaviors and increased rates of overweight, obesity, and diet-related diseases, highlight the “freshman 15” study researchers.

They define healthy dietary behaviors as eating patterns that align with recommended calorie intake and nutritional guidelines, including adequate consumption of fruits, vegetables, and balanced macronutrients.

Conversely, unhealthy dietary behaviors include overeating, under-eating, or a low intake of nutrient-dense foods — particularly when influenced by social or environmental factors.

Social dining encourages eating

The participant pool involved 41 US college students aged 18 to 25 years, from diverse racial and ethnic backgrounds.

They documented their food intake using a dietary tracking app, Nutritionix, and completed daily surveys logging their eating experience. Over four weeks, they recorded 3,168 eating occasions.

Other factors affecting eating behaviors included body mass index, mood, and stress levels. The paper is published in the journal Health.

Recently, separate research investigated how the gut-brain axis influences eating disorders and cravings. A study published in Clinical Gastroenterology and Hepatology found that adults with a disrupted gut-brain interaction are more likely to have restricted food intake disorders.