Introduction The domains of population, health and environment (PHE) function as directly connected systems which determine worldwide sustainability levels. These three elements create a vital connection that helps explain current society's difficulties. The escalating global population creates more pressure on natural resources and healthcare systems as well as environmental stability. The article examines the interactive connection between population expansion and public health results alongside environmental sustainability through an analysis of major population patterns. Population growth creates different health and environmental effects throughout the global regions. Advanced nations encounter multiple difficulties due to their aging society and escalating healthcare expenses and their need for environmentally sustainable urban development. Developing nations face two major population challenges which include excessive births combined with insufficient medical systems and...