Time as a Regulator of Health: Re-examining Human Biological Rhythms Through Ayurvedic Chronophysiology

Time is a fundamental determinant of physiological regulation, yet its role in maintaining health is often underappreciated in contemporary biomedical practice. Modern chronobiology has established that intrinsic biological rhythms, particularly circadian rhythms, govern essential physiological processes, including sleep–wake cycles, endocrine secretion, metabolism, immune function, and cognitive performance. Disruption of these temporal rhythms is closely associated with the development of metabolic disorders, cardiovascular diseases, immune dysfunction, and other chronic health conditions. Long before the emergence of modern chronobiology, Ayurveda recognized Kala (time) as a dynamic regulatory principle influencing physiological equilibrium, adaptation, and health maintenance. This narrative review explores the concept of biological rhythms through the framework of Ayurvedic chronophysiology by integrating classical Ayurvedic concepts with contemporary scientific evidence. Relevant Ayurvedic principles, including Kala, Dinacharya (daily regimen), Ritucharya (seasonal regimen), and Agni (metabolic and digestive function), are critically examined alongside current knowledge in chronobiology, circadian physiology, and metabolic science. Comparative analysis demonstrates substantial conceptual convergence between Ayurvedic temporal principles and modern circadian biology, particularly regarding the temporal regulation of metabolism, endocrine activity, immune responses, and behavioral adaptation. The findings suggest that Ayurveda provides a comprehensive temporal framework that complements contemporary chronobiological research and offers valuable perspectives for optimizing physiological homeostasis. Integrating Ayurvedic chronophysiological principles with modern biomedical understanding may enhance preventive healthcare, facilitate personalized therapeutic approaches, and contribute to the development of chrono medicine-based strategies for improving long-term health outcomes.