Abstract
{ "background": "Adolescent girls in North Africa are at high risk of iron deficiency anaemia, a major public health concern. A national policy mandating the fortification of wheat flour with iron and folic acid was implemented to address this burden, but its longitudinal impact on the target population's biochemical iron status remains unquantified.", "purpose and objectives": "This study aimed to longitudinally assess changes in haematological biomarkers of iron status in a cohort of adolescent girls following the implementation of mandatory wheat flour fortification in urban Morocco.", "methodology": "A prospective cohort study was conducted with urban-dwelling adolescent girls. Venous blood samples were collected at baseline and at two follow-up points to measure haemoglobin, serum ferritin, and soluble transferrin receptor. A linear mixed-effects model was fitted to analyse trends: $Y{ij} = \\beta0 + \\beta1 Time{ij} + u{0i} + \\epsilon{ij}$, where $Y{ij}$ is the biomarker for individual $i$ at time $j$, and $u{0i}$ is the random intercept. Robust standard errors were used for inference.", "findings": "A significant improvement in iron status was observed over the study period. The prevalence of iron deficiency (serum ferritin < 15 µg/L) decreased by 18.2 percentage points (95% CI: 12.5 to 23.9). The model showed a positive, statistically significant temporal trend in haemoglobin concentration.", "conclusion": "The national wheat flour fortification programme was associated with a clinically meaningful improvement in iron status among the studied cohort, suggesting the policy is effective in this urban context.", "recommendations": "Sustained investment in fortification programme monitoring and quality control is essential. Further research should investigate the intervention's efficacy in rural areas and its impact on functional health outcomes.", "key words": "nutritional anaemia, food fortification, public health nutrition, micronutrients