The converging determinants of excessive weight gain in childhood

Abstract

Excessive weight gain in childhood, manifesting across a spectrum from overweight to severe obesity, represents a critical public health challenge of the 21st century. This condition is not a simple consequence of energy imbalance but arises from a complex convergence of determinants operating across multiple levels. This article synthesizes current evidence to argue that childhood obesity is a heterogeneous disorder fueled by the dynamic interaction of biological susceptibility, learned behaviors, and powerful socioecological influences. A deep understanding of this convergence is paramount, as the prevailing paradigm of generic lifestyle advice has proven insufficient to reverse global trends. We examine the foundational role of genetic, epigenetic, and prenatal factors that establish individual metabolic thresholds. Subsequently, we explore how these biological predispositions interface with modifiable behavioral patterns related to dietary intake, physical activity, and sedentary behaviors, which are themselves shaped by familial practices and the broader living environment. Crucially, these behaviors are embedded within and constrained by layered socioecological systems, including household food insecurity, neighborhood design, marketing ecosystems, and macroeconomic policies. The review concludes that effective prevention demands a stratified, systems-oriented approach. Moving beyond one-size-fits-all recommendations, future strategies must integrate biological risk stratification with targeted interventions that address the specific environmental and behavioral drivers prevalent in different populations. This requires synergistic efforts from clinicians, public health professionals, urban planners, and policymakers to create equitable environments conducive to healthy growth for all children.