Introduction: This review article emphasizes the significance of Body Mass Index (BMI) and insulin-like growth factor-1 (IGF1) in evaluating pediatric growth outcomes, particularly for those at risk of undernutrition. The review explores the long-term health consequences of early BMI trajectories, especially their association with cardiometabolic profiles in adulthood. The article also examines the correlation between BMI, insulin-like growth factor 1 (IGF-1), and growth velocity, focusing on their complex interactions in malnourished and obese pediatric populations. Methods: A comprehensive literature search was conducted using PubMed, Google Scholar, and Scopus from 1985 to 2024, focusing on BMI, height growth velocity, IGF1 levels, and the effects of nutritional interventions on pediatric growth outcomes. Studies were included if they focused on children aged 0-18 years and evaluated the impact of BMI and/or nutritional interventions on growth outcomes, with English language articles being prioritized. Review Results: A total of 15 studies involving 4737 participants were analyzed. The review highlights significant findings including the normalization of growth hormone (GH)-IGF axis post nutritional rehabilitation in malnourished children, the rapid response of IGF-1 levels to nutritional interventions, and the influence of protein-rich diets on catch-up growth. Studies also showed that early nutritional support, particularly through human milk, significantly affects IGF-1 levels and that dietary protein intake correlates with IGF-I concentrations and growth in toddlers. Long-term studies indicated that severe malnutrition can have enduring metabolic effects, necessitating sustained nutritional strategies. Discussion: The review highlights the significance of early nutritional support and its impact on IGF-1 levels, which are crucial for healthy growth trajectories. The findings advocate for careful monitoring of early growth rates to optimize long-term health outcomes and stress the importance of adequate protein intake during early childhood. Conclusions: A balanced approach to nutrition, focusing on the interplay between BMI, growth velocities, and IGF1 levels, is crucial in pediatric care. Strategic nutritional interventions, especially those rich in protein, can effectively manage growth outcomes across different BMI categories and improve health trajectories in pediatric populations. This review underscores the need for comprehensive strategies to address nutritional deficiencies and manage growth effectively from infancy through adolescence