Role of Agni in Rasayana Chikitsa: A Conceptual Review

Agni, the fundamental biological principle governing digestion, metabolism, and transformation in Ayurveda, is regarded as the central determinant of health, longevity, and disease prevention. Rasayana Chikitsa, the rejuvenative branch of Ayurveda, aims to preserve health, delay ageing, enhance vitality, and promote immunity through optimal nourishment of body tissues and augmentation of ojas. The present conceptual review explores the intrinsic relationship between agni and rasayana chikitsa based on classical Ayurvedic literature. Classical texts consistently emphasise that the efficacy of rasayana therapy is not independent but is critically dependent on the functional integrity of agni at multiple levels, including jatharagni, bhutagni, and dhatvagni. Proper functioning of jatharagni ensures complete digestion and formation of quality rasa, while bhutagni facilitates elemental and biochemical transformation of nutrients. Balanced dhatvagni enables selective assimilation and qualitative enhancement of tissues, ultimately leading to the formation of ojas. Impaired agni results in ama formation, srotorodha, and ineffective tissue nourishment, thereby diminishing or nullifying the therapeutic benefits of rasayana. This review highlights that rasayana therapy acts primarily through regulation and optimisation of metabolic processes rather than direct rejuvenation. Understanding agni as the central mediator provides a rational foundation for the classical emphasis on purification, dietary regulation, and metabolic assessment prior to rasayana administration. Thus, preservation of agni emerges as the cornerstone for successful rasayana chikitsa and healthy ageing.