Determinants of dietary adequacy and diet quality of in-school adolescent girls in Nigeria: implications for non-communicable diseases

Abstract Background An unhealthy diet is a major risk factor for non-communicable diseases (NCDs), compounded by the rising incidence of overweight/obesity among adolescent girls. This study investigated adolescent girls’ dietary adequacy and quality, their determinants and implications for NCDs. Methods This descriptive cross-sectional study design employed a stratified random sampling technique to obtain data from a validated questionnaire and other assessments. Data was collected in 2023 from 2261 in-school adolescent girls in Nigeria. Dietary adequacy (All-5 food groups) and diet quality (NCD-Protect and NCD-Risk food groups) were assessed in accordance with global dietary recommendation (GDR). Body Mass Index-for-age (BMI) was determined using the WHO growth reference. All analyses were conducted using descriptive and inferential statistics in SPSS Version 27, with statistical significance set at p < 0.05. Results Mean values recorded were age (14.9 ± 1.8), BMI (20.1 ± 3.7 kg/m²), All-5 (3.8 ± 1.1), NCD-Protect (2.4 ± 1.4), NCD-Risk (1.8 ± 1.7), and GDR (9.7 ± 1.5). About 7% were overweight/obese. Older adolescents demonstrated higher GDR (β = 0.20, p = 0.04) scores than their younger counterparts aged 10–13. Adolescents living in urban areas had lower diet quality than their rural counterparts ( p < 0.001), while those from the Southeast region had higher diet quality scores. Large households showed higher All-5, NCD-Protect, and GDR scores than smaller households ( p < 0.05). Girls who took daily money to school had higher All-5 (β = 0.03 to 0.27) but lower GDR scores (β = -0.30 to -0.22) ( p < 0.05). An inverse association exists between All-5 ( r = -0.043, p = 0.039), NCD-Protect food group ( r = -0.054, p = 0.010), and BMI. Conclusion Personal and sociodemographic characteristics influenced the respondents’ dietary adequacy and quality. Higher All-5 and NCD-Protect food group scores lowered BMI. This can positively impact overweight/obesity reduction, thereby delaying NCDs’ onset in later years. Conscious efforts should be made to communicate the potential benefits of improving adolescents’ diets.