Determinants of Folate and Vitamin B₁₂ Deficiencies in Under-Five Children: Insights from the National Nutrition Survey of Pakistan

Background According to the World Health Organization (WHO), worldwide anemia prevalence in children of 6–59 months is 40% [1]. Though iron deficiency is recognized as a significant cause of anemia, vitamin B₁₂ (B₁₂) and folate deficiencies are also important causes. The previous Pakistan National Nutrition Survey (NNS) 2011 showed a high prevalence among women of reproductive age (WRA), which necessitated further investigation in follow-up surveys among children. Methods We performed a secondary analysis of the National Nutrition Survey (NNS) 2018–2019. Blood samples were obtained from 31,828 children (< 5 years), with a subsample analyzed for B₁₂ (n=2693) and folate (n=6690) deficiency. B₁₂ was assessed by electrochemiluminescence immunoassay, and folate by CDC’s microbiologic assay. Logistic regressions were applied to determine factors associated with deficiency. Results 35.1%, while 24.8% of children showed folate and B₁₂ deficiency, respectively. Higher odds of folate and B₁₂ deficiency were observed in Khyber Pakhtunkhwa, OR = 1.424 (95% CI 1.157, 1.752), and newly merged districts of Khyber Pakhtunkhwa, OR = 11.257 (95% CI 2.291, 55.314), respectively. Additionally, mother’s education was associated with B₁₂ deficiency i.e. uneducated OR = 2.017, (95% CI 1.229, 3.308), primary OR = 2.361 (95% CI 1.359, 4.103) and middle OR = 2.108 (95% CI 1.144, 3.882) while underweight was associated with folate deficiency only, OR = 1.181 (95% CI 1.016, 1.371). Conclusion This analysis highlights a considerable burden of folate (35.1%) and vitamin B₁₂ (24.8%) deficiencies among Pakistani children under five years of age, with regional disparities. Socioeconomic and nutritional factors, particularly maternal education and child undernutrition, further influence the risk of deficiency. These results emphasize the need for region-specific nutrition interventions, maternal education programs, and strengthened food fortification strategies.