Nutritional status of school-going adolescent girls is associated with their cognitive function but not academic performance: insights from Ten2Twenty-Ghana baseline study

The link between nutritional status and cognitive performance is well-documented in early childhood, but limited data exist on adolescents, particularly in sub-Saharan Africa. This study examines the associations between nutritional status, overall cognitive function and its subdomains, and academic performance among adolescent girls in Ghana. Cross-sectional data from the Ten2Twenty-Ghana study were analysed, including 845 girls aged 10–17 from 19 primary schools in the Mion District. Fluid cognition, a composite measure of cognitive function, was assessed using the National Institutes of Health Toolbox Cognition Battery. The cognition battery comprised five subdomains: executive function, attention control, processing speed, working memory, and episodic memory. Academic performance was assessed using examination scores in Mathematics, English, and General Science. Anthropometry was used to calculate the body mass index-for-age z-score (BAZ) and the height-for-age z-score (HAZ) using WHO AnthroPlus. Generalised linear mixed-effects models with a random intercept for school, assessed associations while adjusting for potential confounding variables, including age, anaemia, dietary diversity, menarche status, health complaints, school attendance, household food security, wealth, dependency, and literacy ratios, school feeding status, and interviewer effect. The mean HAZ was -0.9 ± 1.2, BAZ was -0.7 ± 0.9, fluid cognition was 26.7 ± 9.6, and academic performance was 53.8 ± 13.1%. BAZ was positively associated with the fluid cognition composite score (adjusted β = 1.12, 95% CI: 0.39, 1.83) and with processing speed subdomain (adjusted β = 1.31, 95% CI: 0.49, 2.13). HAZ was positively associated with processing speed after full adjustment (adjusted β = 0.68, 95% CI: 0.06, 1.29). No significant associations were found between anthropometric indices and academic performance. Nutritional status was positively associated with the fluid cognition composite score and processing speed subdomain among adolescent girls, while no association was observed with academic performance. These findings underscore the importance of improving adolescent nutrition to support cognitive development in rural settings.