Longitudinal Changes in Body Composition and Dietary Intake Among University Freshmen in Ile-Ife, Osun State

The transition from secondary school to university is a critical period during which young adults gain autonomy over food choices, often resulting in dietary changes and shifts in body composition. Longitudinal evidence on these changes among Nigerian university students is virtually absent from the literature. This study tracks changes in body composition and dietary intake among first-year students at Obafemi Awolowo University, Ile-Ife, Osun State, South West Nigeria, over a twelve-month period. A prospective longitudinal cohort study enrolled 280 freshmen aged 16 to 22 years at the beginning of the academic year. Assessments were conducted at enrolment, six months, and twelve months. Body composition was measured using bioelectrical impedance analysis, capturing fat mass, fat-free mass, and total body water. Dietary intake was evaluated at each time point using a 24-hour dietary recall combined with a food frequency questionnaire, with energy and macronutrient intakes calculated. Physical activity level, alcohol use, sleep adequacy, and psychological stress were measured as contextual variables at each wave. Generalised estimating equations were used to model within-subject changes over time, adjusting for sex, faculty, residential status, and baseline measures. The study hypothesises that dietary quality deteriorates and body fat percentage increases over the first academic year, with off-campus residents showing greater adverse changes. Findings will contribute to targeted nutrition interventions for university students during the transition year. Keywords: body composition, dietary intake, university freshmen, longitudinal study, Ile-Ife.