Charaka lays down:”One must always manage to maintain health (swasthya), so that the disturbance (vikara) that have not arisen may not arise” (CS, sutra 5,13). Health, here, is defined by his commentator thus the condition in which one abides well, i.e. without any disturbances whatever. In Ayurveda Charaka’s prescription has two aspects : the causes that promote health, and the causes that interfere with health.
The former is the balance (or equilibrium) of the bodily constituents (mg- writ) while the latter is the imbalance there of (dhatu – vaishamya). Imbalance excites and disturbs.
1) The maintenance of health is accordingly regarded as two fold (1) the body, which constantly being worn out and liable to be thrown out of balance, must be nourished and maintained by good food and correct conduct like a flame being tended by pouring oil to the lamp and by trimming the wick.
(2) The body must also be protected from disturbances, internal and external, by appropriate medication and curative methods, like the flame being guarded from breeze, insects, etc., The latter, viz disturbances, are brought about by internal factors (e.g. the doshas being excited by careless or thoughtless conduct), over which the individual has control, or by external factors (for example seasonal variation , occurrences in nature, ageing) over which he has little control.
Health , thus , is a dynamic concept; it is constantly being subject to factors of disturbance and needs to be restored as often as it is disturbed. It is a continuous process of integration (yoga) of time ( kala), sensory objects (artha) and actions (karma) ( AHr, 1,1,19) time refers to seasonal Variation cold, hot, rain. Sensory Objects are physical stimulation sight , sound, touch , smell and taste. Actions are threefold: bodily ( Physical reactions), mental ( thoughts, fears, wishes etc.,) and vocal ( speech and expressive behaviour). These encompass the substances constituting reality that Charaka spoke of (CS, sutra 1,47) (the three units of time; the five primary elements; direction ( samyyag-yoga) of the three factors (time, sensory objects and actions) is the single causative condition of health. Imperfect integration or association of the same three factors brings about disease.
Association of the three factors could be deficient. excessive or improper. when disease is occasioned. If the weather is proper (cold in cold season, hot in the hot season, and raining in the rainy season), if the sensory objects are just and adequately presented for sensory experience (viz. not straining the sense – organ either by insufficient stimulation or by excessive or unpleasant stimulation) and if the work done by the body and mind is in keeping and the normal needs of the mind, there can be no disturbance whatsoever and disease cannot arise. This is the condition to health.
Integration is further explained in terms of the equilibrium of the doshas, bodily constituents, the digestive fire and the elimination of waste products.
Diseases are two fold: bodily and mental.
Body is the ground for the former while the mind is the ground for the latter. An absense of bodily diseases is bodily health and absense of mental disease is mental health. Thus the balanced functioning of the body and mind is the basis for health in general, which is experienced as ‘ happiness’ or well – being’ (CS sutra, 9,4) The balanced functioning involves the integration of the constituents, viz. the three doshas the seven body – constituents or ingredients of the physical frame and the three gunas. it is in this context that health is describe as prakriti ( nature), borrowing the Samkhya idea of undifferentiated balance of gunas in the primal condition (CHKP on CS, sutra, 9,4).
A pragmatic definition of health is that it is the condition when the digestive fire is nourished ( arogyamvahni – vardhanam’ RN, 20). Good digestion is regarded as symptomatic of good health, for digestive disturbances are at root of most of the ailments. It is in order that the digestive fire may be kept in good shape (viz. neither dull, Manda, nor fierce, ati) that the daily regimen of diet, exercise etc., and the conduct appropriate to seasonal variations are prescribed.
Acharyavagbhatta told that a healthy person is one who what is good, eats moderately and eats only when hungry to the satisfaction of the God.