Health can be defined negatively, as the absence of illness, functionally, as the ability to cope with everyday activities, or positively, as fitness and well-being.

Health is the level of functional and/or metabolic efficiency of an organism at both the micro(cellular) and macro(social) level. In the medical field, health is commonly defined as an organism's ability to efficiently respond to challenges (stressors) and effectively restore and sustain a "state of balance," known as homeostasis. This is a state of balance, with inputs and outputs of energy and matter in equilibrium (allowing for growth). Health also implies good prospects for continued survival. In sentient creatures such as humans, health is a broader concept. Health is a resource for everyday life, not the object of living. It is a positive concept emphasizing social and personal resources as well as physical capabilities.

Another widely accepted definition of health is that of the World Health Organization (WHO), which states that "health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity". In more recent years, this statement has been modified to include the ability to lead a "socially and economically productive life".

In our Best Web Resources Directory, we have the following categories of Health: Alternative Medicine>, Education, Fitness, Food, Medicine, Other.