Early childhood nutrition interventions have been shown to improve cognitive development in children across various regions. A comprehensive search strategy was employed to identify relevant studies, and data were synthesized using a random-effects model with robust standard errors. Findings from this meta-analysis suggest that early childhood nutrition interventions had a significant positive effect on cognitive development, with an estimated mean difference of +0.78 points on standardised test scores (95% CI: +0.52 to +1.04). Early childhood nutrition interventions appear to have lasting benefits for cognitive function. Future research should focus on longitudinal studies and explore the specific mechanisms underlying these effects. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.