Susceptibility to weight gain. Eating behaviour traits and physical activity as predictors of weight gain during the first year of university.

The transition to University has been identified as a possible period for weight gain but few studies have addressed the extent of this experience in UK Universities. The present study was conducted in four Universities in England and Scotland to directly measure changes in body weight, waist circumference and body composition in students during their first year. Two hundred and fifty first-year students completed psychometric eating behaviour questionnaires and a validated physical activity survey before attending one of the laboratories for standardised assessments of height, body weight, waist circumference and body composition at 0, 3, and 12-months. Significant but small and transitory increases in all weight outcomes (e.g. body weight=0.83±2.1 kg) were observed except for fat-free mass. Weight-related measures at baseline predicted changes in weight over 12-months but not 3-months. Disinhibition, power of food and binge eating were associated with change in fat mass while physical activity, cognitive restraint and sensitivity to reward were associated with change in fat-free mass. Weight gain occurs in the first year of University in the UK, but appears to be small and transitory. Changes in fat mass were related to opportunistic eating and the tendency to overconsume, while change in fat-free mass related to physical activity and low dietary restraint in conjunction with drive to experience reward. Psychological markers underlying changes in body composition can inform strategies to promote self-regulation in young adults during a critical life period for weight gain.