Health

      Health is the absence of illness, functionally, as the ability to cope with everyday activities, or positively, as fitness and well-being. In any organism, health is a structure of homeostasis. This is a state of balance, with inputs and outputs of energy and matter in equilibrium (allowing for growth). Health also implies good forecast for continued survival. In sentient creatures such as humans, health is a broader concept.

      The World Health Organization defines health as "a state of total physical, mental and social well-being, and does not consist only of the absence of disease or infirmity." Using the WHO definition classifies 70-95% of people as harmful. A deeper inquiry into the definition of "health" reveals that what makes a cell healthy is sole from what makes an organism healthy.

      Similarly, what makes an organism healthy is unique from what makes a population healthy. To illustrate this point, consider that Japan has the most life expectancy of any nation (2004 UN Human Development Report), despite having one of the highest smoking rates, especially among men (2004 UN Human Development Report).

      The most solid aspects of wellness that fit firmly in the kingdom of medicine are the environmental health, nutrition, disease prevention, and community health matters that can be investigated and assist in measuring well-being.