Prevalence and Impact of Micronutrient (Iron–Folic Acid) Deficiencies on the Health of Adolescent Girls in Coastal Areas of Bangladesh

Background Anemia and iron–folic acid (IFA) deficiencies are major nutritional concerns among adolescent girls in environmentally vulnerable coastal areas of Bangladesh. However, evidence on anemia prevalence and health outcomes relation to IFA supplement receipt remains limited. Objectives This study aimed to assess IFA deficiency-related health problems and the impact of IFA supplementation on hematological, nutritional, and overall health outcomes among adolescent girls in coastal Bangladesh Methods A randomized controlled trial study was conducted among 440 adolescent girls from Patuakhali, Bagerhat, Noakhali, and Cox’s Bazar districts of Bangladesh. In each district, 60 participants were assigned to the IFA intervention group and 60 to the control group. The intervention group received IFA for three months, with assessments of hemoglobin, anemia, nutritional status, and health outcomes. And data were analyzed using IBM SPSS Statistics. Results The prevalence of anemia among participants in the placebo group ranged from 37.5% to 52.0% across the four study districts. After three months of IFA supplementation among intervention group, anemia prevalence decreased to 2.0% in Patuakhali, 2.2% in Bagerhat, 0% in Noakhali, and 4.7% in Cox’s Bazar. The intervention group showed significantly higher hemoglobin concentration compared with the placebo group (12.20 ± 0.30 vs. 11.96 ± 1.18 g/dL; p < 0.001). Significant improvements were also observed in mid-upper arm circumference (24.20 ± 4.12 vs. 22.58 ± 2.88 cm; p < 0.001), platelet count (p < 0.001), and anemia-related symptoms, including dizziness (p < 0.001), infection symptoms (p < 0.001), and pale skin/gum symptoms (p = 0.027). Furthermore, IFA supplementation was associated with improved iron-rich food intake, nutrition knowledge, vitamin/mineral awareness, and iodized salt use. Conclusion Anemia remains prevalent among adolescent girls in coastal Bangladesh. IFA supplementation was strongly associated with a lower likelihood of anemia, highlighting the potential importance of strengthening adolescent supplementation, nutritional screening, and adherence-focused interventions in vulnerable coastal populations. Trial registration ClinicalTrials.gov, NCT07903558. Date of registration 21102026.