This chapter argues that the Planetary Health approach provides the most effective and integrative framework for addressing today’s complex socio-environmental challenges. We examine how Planetary Health uniquely unifies related health approaches, addresses disruptions from climate change, and tackles pressing issues in nutrition, food security, and disease emergence within the health sector. Through a narrative literature review of 57 PubMed articles (2015–2025), eight AI-sourced articles, and 16 from supplementary searches, we found that realising Planetary Health’s promise depends on global collaboration and systemic transformation in response to planetary crises such as climate change, pollution, and biodiversity loss. We further contend that leveraging the complementary strengths of conceptual frameworks—One Health, Global Health, Public Health, and Eco Health—while prioritising sustainable lifestyles and broad sociocultural perspectives, is essential. Our findings highlight that building global competence via transdisciplinary approaches in public health and nutrition is crucial for effecting transformative change.