Effects of Malnutrition on Immune Deficiency in Infants in Northern Nigeria

This study examined the effects of malnutrition on immune deficiency among 450 infants aged 0–24 months across five Northern Nigerian states using a cross-sectional design with a nested case-control approach. Anthropometric measurements, immunological parameters (including lymphocyte subsets, immunoglobulin levels, and cytokine profiles), dietary assessments, and socioeconomic data were collected and analyzed using STATA 17. The findings revealed that 35.6% of infants were stunted, 23.8% underweight, and 18.2% wasted, with severe stunting in 14.2% of cases. Malnourished infants exhibited significantly reduced immune function, including lower CD4+ T-cell counts (824 ± 312 vs. 1,356 ± 286 cells/μL, p<0.001) and IgG levels (5.8 ± 1.9 vs. 8.3 ± 1.6 g/L, p<0.001), along with elevated pro-inflammatory cytokines and increased anergy (68.3% vs. 23.5%, p<0.001). These immunological impairments were strongly associated with higher infection rates—mean illness episodes reached 3.8 among severely malnourished infants compared to 1.4 in well-nourished peers (p<0.001). Multivariate regression confirmed stunting and wasting as independent predictors of immune suppression and increased disease susceptibility. The study concludes that malnutrition significantly compromises immune function in infants through both cellular and humoral pathways, exacerbating infection risk, and calls for integrated interventions addressing nutritional, socioeconomic, and environmental determinants to improve child health outcomes in Northern Nigeria.