Changes in weight and body composition during the first semester at university. A prospective explanatory study

The purpose of this study was to objectively assess changes in weight, BMI, body composition and waist circumference during the first semester at university in Belgian students, as well as to identify correlates of change in BMI and fat%.

Weight, height, body composition and waist circumference were measured at baseline (October/November 2011) and follow-up (February/March 2012) in 101 first year university students. Additionally, a health behaviour questionnaire was completed at follow-up.

After one semester at university, students gained on average 1.0 kg (range=-4.1 kg, +7.7 kg) of body weight consisting of 0.8 kg of fat mass. In contrast, fat free mass and waist circumference did not change. Regression models showed that being male, higher amount of TV/DVD watching and higher frequency of eating at a friends' place were contributors of BMI increase, whereas living in a student residence and lower frequency of reading and studying was related with higher increases in fat%.

This is the first European study demonstrating that the first semester at university is a critical period for weight and fat gain. Future intervention studies should have special attention for male students and students living in student residences, and focus on promoting healthier food choices when eating out-of-home.