The concept of Health is somewhat difficult to understand. When we say a person is healthy, it means to the lay man that the person is normally doing his activities and does not outwardly show any signs of any disease in him. However, for the medical man it denotes the conformity to certain standards like physical measurements, biochemical norms and rates, physiological standards, etc. Even these standards vary with race, rest, exercise, food, habits, starvation, climate, altitude, latitude, etc. It has been extremely difficult for scientists concerned with human biology to lay definite criteria for health and define the term Health in a specific manner.
From the history of medicine we know that there have been various systems of medicine or healing arts evolved in different parts of the world during different civilizations. But in no system has there been a clear-cut definition of health.
In the oxford dictionary health means the state of being free from sickness, injury or disease, bodily conditions; something indicating good bodily condition. A few decades ago this meaning was conveyed in the definition of health but recently the World Health Organization have considered it necessary to give a direction towards the achievement of a robust and happy and active bodily and mental condition capable of continuous productive ability and, therefore, have defined health as follows:
“Health is a state of complete physical, mental and social well being and not merely an absence of disease or infirmity.” (WHO—1948) it will be seen that even after having this definition it will be difficult to conceptualise and standardise positive health with specific clear-cut attributes and criteria for measurement. A person may be enjoying mental equanimity and enthusiasm for doing anything. He may also be physically able to do any amount of work, but he may be having some minor dysfunction or deficiency or even a mild infection causing a very minor disturbance which however does not upset his normal activities.
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