a complete state of physical, mental, and social well-being and not merely the absence of disease or infirmity — World Health Organization (1948)

it is a balance among physical, mental, and social well-being

So, health is -

  • absence of disease
  • proper functioning of organs and systems
  • able to do daily activities without limitations
  • has many components; mental, physical, and social

involves aspects such as regular exercise, balanced nutrition, sufficient sleep, and the absence of physical symptoms or illnesses.

wellness = usually means optimum state of health


Illness on the other hand is

  • deviation from normal well-being
  • presence of disease or physical symptoms
  • poor health
  • impaired functioning

According to WHO,

“Illness is a state in which a person’s physical, intellectual, emotional, social or spiritual functioning is diminished or impaired in comparison with the previous experience”.”

It is a state of poor health where normal functioning of the body is disrupted