Concept of Health, Diseases and illness

Healthcare depends critically on people being healthy. Human productivity and progress depend on people's general health and well-being. All of this is crucial to progress in industry and science. The concept of health is not universally shared. In its modern sense, health refers to a state of complete physical, mental, and social well-being rather than only the absence of illness or disability.

It's true that most individuals struggle to define the term "health," even if they all seem to agree on its meaning.

According to "Oxford English Dictionary," health means soundness of body or mind; that condition in which its functions are duly and efficiently discharged.

Webster: The conditions of being sound in body, mind, and spirit especially freedom from physical disease or pain.

According to WHO, 1948, "Health is a state of complete physical, mental, social and spiritual wellbeing and not merely an absence of disease and infirmity." health is not only the absence of disease but also the absence of non-manifest and undiagnosed disease or impairment.

The concept and definition of health have changed over time. Different experts have viewed health according to their own fields of interest. A brief account of the changing concepts of health has been given below.

Definition of Health

The condition of being sound in body, mind, or spirit, especially free from physical diseases or pain - Webster

A state of relative equilibrium of body forms and function which results from its successful dynamic adjustments to forces tending to disturb it. It is not a passive interplay between body substance and forces infringing upon it, but an active response of the body forces working towards adjustment  - Perkins

Health is an achievement of a state of harmony between man's internal and external milieu -  Liverpool School of Tropical Medicine

WHO defines health "as a state of complete physical, mental and social wellbeing and not merely an absence of disease or infirmity". The definition also covers the person's ability to lead a socially and economically productive life.

WHO's definition is positive and includes more than physical health. It infers that health is an absolute or ultimate state. However, all individuals cannot achieve the same level of health because of innate differences as some of us are born with physical and mental limitations. According to WHO, complete well-being for all is unattainable.

WHO's the definition of health has the following characteristics:

• A concern for the individual as a total system
• A view of health that identifies the internal and external environment
• An acknowledgment of the importance of an individual role in life.

Health in its broadest sense is a dynamic state in which the individual adapts to change in the internal and external environment, to maintain a state of well-being. The internal environment includes many factors that influence health, including genetics and psychological variables, intellectual and spiritual dimensions, and disease processes. The external environment includes factors outside the person that may influences health including physical environment, social relationships, and economic variables. It is because both environment change continuously and the person must adapt to maintain a state of well-being.

Optimum /Positive health

Health is a continuum with optimum health on the one end and death on the other end.  All people fall somewhere on the continuum depending on their level of health or illness.

The state of positive health implies the notion of perfect functioning of the body and mind. It doesn't simply mean the absence of disease or the provision of diagnostic, curative, and preventive services. It refers to the state of complete physical, mental and social well-being as defined by WHO. It conceptualizes health biologically as a state in which every cell and every organ is functioning at optimum capacity and in perfect harmony with the rest of the body. Similarly psychologically the individual feels a sense of perfect well-being and of mastery over his environment and society as a state in which the individual's capacities for participation in the social system are optimal.

Optimum/positive health has been criticized by many experts as the concept of positive health cannot become a reality because man will never be so perfectly adapted to his environment. A person's life involves so many struggles, failures, and sufferings. Health is described as potentiality: the ability of an individual or a is described social group to modify him or herself continually, in the face of changing conditions of life. 

Changing the concept of Health:

Biomedical concept

According to this concept, health has been viewed as an absence of diseases. This concept stresses the germ theory of disease, i.e. disease or ill health is caused due to disease-causing organisms. If a person is free from diseases, then s/he was considered healthy. However, this theory has been rejected by other scientists because it will not help to explain some of the major health problems which are primarily not due to disease-causing organisms, for example, malnutrition, mental illness, drug abuse, accidents, chronic illness, environmental pollution, etc. This concept has minimized the role of environment, social, and psychological cultural determinants Developments in medical and social sciences led to the conclusion that the biomedical concept of health was inadequate and gave rise to other concepts.

Ecological concept

Ecologists viewed health as a dynamic equilibrium between man and his environment and disease maladjustment of the human organism to the environment. The environment includes air, water, and other necessary things needed by human beings for their life e.g. Health problems arising from a polluted environment. Ecologists argue that human ecological and cultural adaptations don't determine only the occurrence of disease but also the availability of food and population explosion. They further argue that improvement in human adaptation to natural environments can lead to longer life expectancies and a better quality of life even in the absence of modern health delivery services.

Psychological concept

 Sociologists viewed health not only as a biomedical phenomenon but also that is influenced by various factors like social psychological, cultural, economic and political factors of the people concerned. These factors must be taken into consideration in defining and measuring the state of health and health should be taken as both biological and social phenomenon.

Holistic concept

The holistic model is the output of all the above concepts. It recognizes the strength of social, economic, political, and environmental influences on health  According to this concept health is viewed as a multidimensional process involving the well-being of a whole person in the context of the environment. The emphasis is on the promotion and protection of health. The holistic approach implies that all sectors of society have an effect on health, for example, agriculture, animal husbandry, and industry. education, housing, communications, public works, society, and its cultures.

Concept of Disease

Webster defines disease as "a discomfort, a condition in which bodily health is seriously attacked, deranged or impaired, a departure from a state of health, an alteration of the human body interrupting the performance of vital functions."

The Oxford English Dictionary defines disease as "a condition of the body or some part, or organ of the body in which the functions are disturbed or deranged.

The disease can be defined from various points of view such as ecological, sociological, and others, etc. Every disease has one or more causes. For some diseases cause is known whereas for the cause is unknown.

In many cases, terms such as disease, disorder, morbidity, sickness, and illness are used interchangeably. There are situations, however, when specific terms are considered preferable. Disease. The term disease broadly refers to any condition that impairs the normal functioning of the body.

Definition of disease

Medical Definition of Disease. Disease: Illness or sickness characterized by specific signs and symptoms.

There have been many attempts to define the disease.

Webster defines disease as "a condition in which body health is impaired, a departure from a state of health, an alteration of the human body interrupting the performance of vital functions."

The Oxford English Dictionary defines "disease as a condition of the body or some part or organ of the body in which its functions are disrupted or deranged". From an ecological point of view, the disease is defined as the "a maladjustment of the human organism to the environment"

The distinction is also made between the words disease, illness, and sickness which are not wholly synonymous. The term "disease" literally means "without something is a wrong bodily function. 'Illness" refers not only to the presence of a specific disease but also to the individual's perceptions and behavior in response to the disease, as well as the impact of that disease of the psychosocial environment.

"Sickness" refers to a state of social dysfunction Susser has suggested the following usage:

 The disease is a physiological/psychological dysfunction; IIness is a subjective state of the person who feels aware of not being well; Sickness is a state of social dysfunction i.e.a role that the individual assumes when ("sickness role").

The clinician sees people who are ill rather than the diseases which he must diagnose and treat. However, it is possible to be a victim of disease without feeling ill and to be ill without signs of physical impairment. In short, an adequate definition of disease is yet to be found - a definition that is satisfactory or acceptable to the epidemiologist, clinician, sociologist, and statistician. 

Definition of Illness

Illness is a broad term that defines the poor state of mind, body, and, to a certain extent, spirit. It is the general feeling of being sick or unwell (outside the person's belief of good health).

Spectrum of Health and Illness

Health can be described as the absence of disease is inadequate and unsatisfying according to the presence of certain lesions, or the presence of "abnormal" readings measured by instruments of investigation. Illness is a related, but different, term from disease. It is used mainly to refer to the experience of being unwell, incorporating our concept of disease, but actually describing the subjective experience of a person. Only a person can tell they feel nauseated, or that they have pain. Instruments won't reveal those phenomena. Similarly, health should be understood as a phenomenon, or an experience, in its own right. Consider these three concepts as a spectrum

H= Health; A= Acute disease; C= chronic illness