Health refers to the state of one's physical, mental and social well-being. It is a condition of complete wellness that helps one lead a full, active and productive life. To promote health, a person can reduce his or her risk of developing a disease or illness by making appropriate lifestyle choices. In addition, avoiding unhealthful situations can also contribute to promoting health.

Modern concepts of health recognize the human capacity for self-fulfillment and self-realization. This is an important goal of the World Health Organization's Global Strategy. Although disease and illness are recognized as common factors affecting the health of individuals, it is important to note that the underlying causes are different for each person. Some of these include structural influences, while others are due to individual choices.

During the Middle Ages, the perception of health was strongly influenced by religion. Hippocrates, for example, explained health in terms of environmental factors. He believed that the seasons affected both the mind and the body, and that proper diet and exercise are essential for maintaining good health.

Ancient Chinese medicine and Indian medicine also had similar concepts. However, the perception of health was very different in these societies. Instead of focusing on the whole person, the ancient Chinese and Indian physicians emphasized the functional components of health, such as the harmonious functioning of organs.

The ancient Greeks, on the other hand, viewed health as a balance of the soul and the body. They believed that illness and health are a natural result of adaptation. Moreover, they also saw a connection between the human spirit and the environment.

During the Renaissance, the idea of health was further reframed. This perspective recognized the need for a holistic approach, incorporating elements of nature, function, and individualism. A lay perspective on health, in contrast, is characterized by pragmatism and individualism.

As a result, there is a wide variety of definitions of health. One can choose from operational, quantitative, or qualitative definitions. There are also many other approaches.

The World Health Organisation defines health as "a state of complete physical, mental and social well-being". It also states that health is a fundamental human right. Therefore, it is important to maintain and enhance the health of the community, and the enjoyment of the highest attainable standard of health is a basic right for all.

A healthy lifestyle, such as proper nutrition, adequate sleep, and exercise, improves the health of an individual and his or her ability to perform the daily routine. Furthermore, a healthy lifestyle allows people to live longer, and thus saves them from costly medical treatments and hospital visits.

While it is possible to take health for granted when it is in its pristine state, health is constantly challenged by changes in the environment, such as stress and illness. This is why a good definition of health must allow for the possibility that health and illness can be affected by change.

Many researchers argue for more standardized and practical definitions of health. These approaches can help to shape the content of the concept and its boundaries.