Abstract
BACKGROUND: Adolescent malnutrition is a major public health problem, yet sex-specific determinants such as lifestyle behaviors remain understudied. This study examined gender differences in dietary habits, lifestyle behaviors, and nutritional status among private high school students in Addis Ababa, Ethiopia. METHODS: A cross-sectional study was conducted among 283 adolescents aged 14-19 years, randomly sampled from three private schools between October 2022 and June 2023. Data on socio-demographics, diet, and lifestyle were collected using a structured questionnaire. Anthropometric measurements classified nutritional status as stunted (height-for-age Z < - 2 SD), underweight (BMI-for-age Z < - 2 SD), overweight (BMI-for-age Z + 1 to + 2 SD), obese (BMI-for-age Z > + 2 SD), or well-nourished. Z-scores were computed using WHO AnthroPlus. Chi-square tests compared sex differences, and logistic regression identified predictors of nutritional status. RESULTS: Based on BMI-for-age, 50.5% of adolescents were well-nourished (- 2 SD to + 1 SD), 11.5% were underweight ( < - 2 SD), 26.2% were at risk of overweight (+ 1 to + 2 SD), and 5.7% were overweight ( > + 2 SD). Nearly 60% had poor dietary diversity, one-third skipped meals, and 49.5% had unhealthy weight. Boys were more physically active (≤ 1 h/day: 45.4% vs. 54.6%, p = 0.001) but more likely to skip meals (p = 0.04) and frequently consumed cakes and biscuits (p = 0.02). Girls reported higher fast-food intake (≥ 4 times/week) and longer screen time (> 2 h/day), though not significant. Among boys, younger age (14-16 years) increased odds of being well-nourished compared with older boys (AOR = 2.26, 95% CI: 1.12-4.60, p = 0.025). Among girls, frequent fast-food intake (AOR = 0.32, 95% CI: 0.10-1.00, p = 0.05) and screen time (AOR = 0.43, 95% CI: 0.20-0.94, p = 0.035) predicted suboptimal nutrition. Negative body image (AOR = 1.83, 95% CI: 1.13-2.98, p = 0.01) and screen time > 2 h/day (AOR = 0.60, 95% CI: 0.37-0.98, p = 0.04) were predictors for both sexes. CONCLUSIONS: Adolescent nutrition is shaped by shared and gender-specific factors. Body image and screen time influence both sexes, while younger age benefits boys and fast-food intake harms girls. Gender-responsive, school- and family-based interventions are needed.