Health, as defined by the World Health Organization, is a condition whereby “a state of total physical, mental and emotional well-being”. Various definitions have also been applied for various purposes over the years. A general view is that health is the state in which an individual’s physical health meets the needs and expectations of his or her emotional health. A major portion of the population seeks to attain a state of health; therefore, the definition of health has become one of the most important factors for defining one’s level of happiness or unhappiness.

There are many explanations for the emergence of the concept of definition of health. The introduction of genetics and germ cells into our environment is one of the major causes. In fact, all diseases are the result of a combination of genes, environment, and lifestyle that result in an individual’s characteristics (which we call the traits) that determine his or her likelihood of contracting a certain disease. Hence, when an individual is diagnosed with a certain disease, there is an obvious connection between the person’s current state of health and the possibility of contracting that disease. It may be difficult to make the link between a person’s good health status and the presence of certain diseases, but it is still very much there.

The second major cause of the emergence of the third definition of health is the recognition of a genetic contribution to a person’s health conditions and to his or her life course. The presence of several diseases within a family is now recognized as a factor that may contribute to a person’s chances of acquiring a certain disease. A contributing factor may not always be identified, since there are many interconnecting factors that contribute to an individual’s life course and to his or her health conditions. However, it is possible to identify common disease associated factors that can help in designing improved prevention and care strategies for such conditions. Prevention and care programs focus on conditions that are commonly acquired, because only when a disease is acquired it is possible to identify its etiology and devise appropriate preventive measures.