Objectives This systematic review aimed to evaluate the effectiveness of nutrition-specific interventions in improving child linear growth and reducing stunting during the first 1,000 days of life. Methods A systematic review was conducted in accordance with PRISMA 2020 guidelines. Searches were performed in PubMed/MEDLINE, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials for studies published up to September 2025. Randomized controlled trials, cluster-randomized trials, cohort, and quasi-experimental studies assessing nutrition-specific interventions were included. Due to substantial heterogeneity across studies, findings were synthesized narratively. Results Thirteen studies conducted in Asia, Africa, and Latin America were included. Nutrition-specific interventions, particularly lipid-based nutrient supplements, fortified foods, and food-based strategies, were associated with modest improvements in length-for-age z-scores and reductions in stunting prevalence. Larger effects were observed when interventions were initiated early in life and implemented in settings with high baseline stunting and food insecurity. Conclusion Nutrition-specific interventions can contribute to improvements in child linear growth, especially when delivered early and sustained during the first 1,000 days. However, effect sizes vary by context, underscoring the importance of integrated and context-sensitive implementation strategies.
Salim et al. (Wed,) studied this question.