Question : What is Health and why should we care?

My idea here is to form a hypothesis concerning what constitutes health, good health, optimal health or even excellent health and then to investigate and develop a paper around this to confirm the hypothesis.
Many factors for sure need investigation and immediately two come to mind, internal environment and external environment; in other words what you live in and what lives in you are important facets of health, good or bad.
I am very open to ideas to form the hypothesis and realize that this is not a new subject but over 5000 years old already but now we are increasingly dying from personal lifestyle choices even with the understanding that these choices are making us sick. Some might have no choice or few choices. An example is people incarcerated for crimes, food is given, drinks are given, the psychological conditions and exercise options are clearly external environmental factors, but what of the internal, food, disease, water, drinks? Choices can probably still be made. For those with choices concerning our external environment, do we make good choices and if so what does that mean?
Psychological conditions are an internal factor affected clearly by external lifestyle factors so need consideration also.
Having spent just a few days looking at Health Coaching programs, there is a lot of choice and variety about what a Health Coach should be qualified in and able to teach. Even a yoga teacher has to undertake months of training to be able to teach a yoga practice and this aspect of health is probably a smaller impact than perhaps food and water or stress. Nonetheless a factor to be taken seriously is movement and as the investigations continue we shall find the answers to movement.
Just like heart attacks are a symptom of something being wrong with health, and not the cause, investigations of the causes could lead to better outcomes for future generations. Many diseases and modern lifestyle causes for poor health and death are often symptoms not causes and it is the causes we seek so that changes can be made to behavior for our health and wellbeing.
I plan to continue this meta-research and first develop the hypothesis so that the factors causing poor health can be determined and a better way found for a healthier life into old age.
Until then ciao. Dai