In common usage and medicine, health, according to the World Health Organization, is "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity". A variety of definitions have been used for different purposes over time. Health can be promoted by encouraging healthful activities, such as regular physical exercise and adequate sleep, and by reducing or avoiding unhealthful activities or situations, such as smoking or excessive stress.
Well-being, or wellbeing, also known as wellness, prudential value, prosperity or quality of life, refers to what is intrinsically valuable relative to someone. So the well-being of a person is what is ultimately good for this person, what is in the self-interest of this person. Well-being can refer to both positive and negative well-being. In its positive sense, it is sometimes contrasted with ill-being as its opposite.
Health equity arises from access to the social determinants of health, specifically from wealth, power and prestige. Individuals who have consistently been deprived of these three determinants are significantly disadvantaged from health inequities, and face worse health outcomes than those who are able to access certain resources. It is not equity to simply provide every individual with the same resources; that would be equality. In order to achieve health equity, resources must be allocated based on an individual need-based principle.
Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals". Analyzing the determinants of health of a population and the threats it faces is the basis for public health. The public can be as small as a handful of people or as large as a village or an entire city; in the case of a pandemic it may encompass several continents.
Health education is a profession of educating people about health. Areas within this profession encompass environmental health, physical health, social health, emotional health, intellectual health, and spiritual health, as well as sexual and reproductive health education. Health education can be defined as the principle by which individuals and groups of people learn to behave in a manner conducive to the promotion, maintenance, or restoration of health.
