CHRONO-NIDRA: A HEALTH CARE FRAMEWORK FOR NIDRA (RESTFUL SLEEP) THAT IS CHRONOBIOLOGICALLY ALIGNED

Background: Ayurveda places Nidra (sleep) among the Trayopastambha, the three supportive pillars of life. Classical Ayurvedic descriptions connect appropriate sleep with sukha (well-being), pushti (nourishment), bala (strength), jnana (knowledge) and jivita (life), while improper sleep is associated with adverse states. Contemporary sleep science increasingly conceptualizes sleep as multidimensional, including duration, continuity, timing, regularity, architecture and daytime functioning. The proposed Chrono-Nidra framework explores whether the classical emphasis on appropriate timing and regulated daily conduct can be operationalized through modern chronobiology. Objective: To develop the Nidra-Circadian Alignment Model (NCAM), a testable conceptual framework linking Ayurvedic Dinacharya/Ratricharya principles with the endogenous circadian timing system, and to propose a preliminary Nidra Circadian Alignment Index (NCAI). Methodology: An integrative conceptual review was undertaken using the supplied presentation as the primary conceptual source for the framework, classical Ayurvedic references concerning Nidra and regulated daily/night routines, and contemporary peer-reviewed literature on sleep regularity, circadian disruption, light exposure, cardiometabolic health and sleep health. The framework maps Ayurvedic constructs to measurable modern variables without assuming equivalence between traditional and biomedical concepts. Key synthesis: Modern evidence indicates that sleep health is not adequately represented by duration alone. Sleep regularity and timing have independent associations with cardiometabolic and cardiovascular outcomes, while circadian disruption can affect endocrine, metabolic and autonomic physiology. Light is a major environmental synchronizer of the circadian system. These findings provide scientific plausibility for investigating, rather than proving, whether time-structured Ayurvedic routines may support circadian alignment. Proposed model: Chrono-Nidra is operationally defined as sleep with sufficient duration, adequate continuity/architecture, temporal consistency, and alignment with environmental light–dark exposure and individual circadian phase. NCAM proposes a cycle of appropriately timed daytime light exposure, stable wake timing, evening reduction of stimulating light, sleep at a biologically appropriate phase, and nocturnal restoration. Conclusion: NCAM is a hypothesis-generating framework rather than a demonstrated clinical intervention. Its principal contribution is to convert the broad Ayurvedic idea of well-regulated Nidra into a measurable, falsifiable research model. Future studies should prospectively test the NCAI using actigraphy, sleep diaries, light exposure measurement, DLMO or other circadian phase markers, and metabolic/autonomic outcomes.