EC Paediatrics

Vitamin B12 is essential for immune-cell function and DNA synthesis. In children, adequate Vitamin B12 is critical for balanced immune development. About 60% of young populations in developing economy are affected by widespread deficiency of this important vitamin. This review examines how Vitamin B12 status influences immune regulation and infection severity in pediatric populations. A systematic review of the published literatures were conducted, including review studies and experimental research on Vitamin B12 and immune function in children. Databases were searched for observational studies examining Vitamin B12 impacts on lymphocyte profiles and infection severity in pediatric populations. Deficient Vitamin B12 status is associated with immune alterations. For example, Vitamin B12 deficient infants have been shown to have reduced regulatory T-cell percentages. Immunology studies have reported that Vitamin B12 deficiency causes decreased CD8+ T-lymphocyte counts and suppressed natural killer (NK) cell activity. Correspondingly, administration of methylcobalamin restores CD8+ and NK-cell levels. Vitamin B12 also influences cytokine networks. It downregulates inflammatory mediators and augments antiviral cytotoxic responses. In clinical cohorts, Vitamin B12 supplementation in deficient infants led to significant reductions in pro-inflammatory cytokine levels. Insufficient Vitamin B12 appears to tip the immune balance toward dysregulated cytokine profiles and weakened pathogen defense. Vitamin B12 is a key immunomodulator in pediatric health.

Keywords: Vitamin B12; Cytokines; Infection; Pediatric

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