Dietary habits, nutritional knowledge, and anthropometric indices of adolescents attending public secondary schools in Ogun State, Nigeria

Abstract

Background: Adolescence is a critical period of heightened nutritional vulnerability. Dietary habits and nutritional knowledge during this stage shape long-term health outcomes, yet evidence among public secondary school adolescents in Southwest Nigeria remains limited. Objective: This study assessed dietary habits, nutritional knowledge, and anthropometric indices of in-school adolescents attending public secondary schools in Abeokuta North Local Government Area, Ogun State, Nigeria. Methods: A descriptive cross-sectional design recruited 300 adolescents aged 10–19 years from six public secondary schools using multi-stage random sampling. Data were collected via a structured interviewer-administered questionnaire covering sociodemographic characteristics, dietary habits, and nutritional knowledge. Nutritional status was assessed using Body Mass Index-for-age (BAZ) and Height-for-age Z-scores (HAZ) computed with WHO AnthroPlus. Chi-square and Fisher's exact tests examined associations at p < 0.05. Results: Most participants were older adolescents (79.7%; mean age 15.67 ± 2.50 years), predominantly female (64%), from low socioeconomic households. Meal skipping was prevalent (44%), with lunch most frequently omitted; home-prepared meals (92%) and high fried food intake (84%) were common. Low nutritional knowledge was found in 80.3% of participants, with no significant age-related difference. Stunting affected 37.0%, while thinness (68.0%) and severe thinness (12.0%) were markedly elevated. Household size was significantly associated with HAZ (χ² = 12.82, p = 0.012) and BAZ (χ² = 18.47, p < 0.001). Maternal educational level was significantly associated with BAZ (χ² = 13.56, p = 0.009). Conclusions: A high burden of undernutrition coexists with poor dietary habits and low nutritional knowledge among adolescents in Abeokuta North. Household size and maternal education are key structural determinants of nutritional status. Targeted school-based nutrition education and household-level food security interventions are urgently needed.