Problems with the WHO definition of 'health'
This is a section of a larger paper discussing problems in health care distribution
The World Health Organisation  defines health as "...a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity."  In doing so it incorporates total well-being under the concept of health. This definition is not a relational claim between the various parameters of total well-being and a more limited range of components identified as health. Rather, it is an identity claim such that an individual is not truly healthy unless they have complete wellbeing. In this instance, the idealized condition of complete well-being and the concept of health are synonymous.
While the WHO definition has been under sustained attack almost since its inception, it continues to be extremely pervasive in its influence and echoes of it are found in most welfare approaches to the definition of health. Strictly speaking, it is unlikely that the formulators of this definition envisaged it as a subjectivist account. However, since it does in fact identity 'health' with subjective wellbeing, problems associated with this account can be assumed to illuminate problems with subjectivist accounts of health more generally.
As Daniel Callahan notes one of the principal attractions of such a definition is its resistance to Dualist versions of the self.  In our ordinary lives we do not normally make absolute distinctions between the good of our bodies and the good of ourselves. It is certainly possible to have poor physical wellbeing and yet maintain high levels of subjective wellbeing. Some individuals apparently remain happy despite crippling ailments. Equally, it is possible to be suffering from a physical ailment and not be aware of this. Our subjective sense of wellbeing in this case does not seem adversely affected by our physical condition. More usually however, illness, injury and disability are at odds with our subjective wellbeing. Typically, when our body suffers so do we. Indeed, unless the good of our bodies is linked in some fundamental way to our subjective sense of wellbeing, it is difficult to see why we would value physical wellbeing as such, as distinct from what physical wellbeing can do for us. The WHO definition asserts this intrinsic relationship between the self and the body by making the good of one's body and the good of oneself indistinguishable. Since we usually experience ourselves as whole entities rather than component parts the WHO definition closely emulates the framework within which individuals ordinarily experience their own lives.
Because the WHO definition places emphasis on the individual's subjective experience it can also account for the differing levels of importance placed on particular physical conditions by different individuals. A condition that is of little significance to one individual may have a devastating impact on the life of another. The loss of the end joint of a little finger may be little more than a cosmetic inconvenience to one individual but may destroy the career of another. Although the physical condition is the same for both individuals, it will clearly have a different impact on their levels of total wellbeing. A theory of health that acknowledges that such differences can have some level of moral importance has intuitive appeal.
One further attraction of the WHO definition lies in its recognition of the observable relationship between the total environmental context of the individual and the individual's physical wellbeing. It has already been observed that the treatment of disease and disability has had less overall impact on the morbidity and mortality levels of populations, than general improvements in social and environmental conditions. It is not unreasonable therefore to hold that the physical wellbeing of individuals is as well served by focusing on the conditions that generate wellbeing in general, than it is by simply focusing on the current physical condition of the individual. While the WHO definition has its attractions, the inclusion of all these components of wellbeing under the one concept of 'health' creates considerable problems for any attempt to delineate health care needs.
Insistence on the condition of 'completeness' within each of the components of well-being and across the range of components that make up total well-being, is perhaps the definition's most prominent flaw. It suffers from problems common to maximizing principles in general. In the first instance it is unclear how we should measure 'completeness' within each of the parameters of well-being. The definition does not indicate whether we should understand the condition of completeness as a measure of individual potential or as an intersubjective measure but in either case it immediately runs into problems. A consideration of physical well-being will illustrate the difficulties although similar problems can be expected to arise under each of the other components of total well-being.
If we use an intersubjective measure and decide that the condition of completeness is to be measured by reference to some exemplar of fitness, then most people will, by definition, fail to reach this level. If we use such a high standard then only elite athletes will have complete physical well-being. We cannot object that elite athletes are the wrong standard to use in this case, since the status of such athletes is itself an indication of the upper limits of human capacity. Falling short of such a standard is to fail to reach the potential that human beings as a species have for physical well-being. Complete physical well-being, i.e. 'health', under this measure seems therefore to be by definition, unobtainable for most people.
However, if we use the maximum fitness potential of each individual as a measure of complete physical well-being, we encounter another problem. The fitness potential of some individuals is very low. Severely disabled individuals for example, have extremely limited physical capacitates. Nonetheless, provided such individuals reach their maximum potential we appear committed to the view that they have complete physical well-being under this measure. It cannot be argued in this case that disability is itself an indication of a lack of complete well-being, since this would be simply to revert to an intersubjective measure of completeness with the difficulties previously described. Even if we imagine a world in which there is no disability, itself an implausible scenario, there would still presumably be variation in individual capacities. Determining the upper limits of each person's capacity will therefore become a problem. If an individual's physical well-being can be improved then they do not have complete well-being and under the WHO definition cannot be entirely healthy. However, unless everyone is engaged in continuous, fully effective physical training, we cannot be sure that any given individual's physical well-being could not be further improved. Indeed, determining whether or not a particular training schedule is effective in itself seems to require an intersubjective standard of physical well-being. In any case we seem to be left with a bizarre outcome. Either we can never be sure whether or not individuals are healthy, or we are committed to spending all our time and energy discovering whether they are or not. Whichever way we choose to measure the condition of 'completeness' within each of the parameters of well-being, the outcomes are counter intuitive.
The insistence on an idealised level of full functioning across the range of well-being criteria also encounters another problem that is common to other maximising principles.  Although there are no absolute divisions between the various components of total well-being, such components are nonetheless sufficiently independent of one another to often operate as separate variables. Thus, it is possible for us to have low levels of well-being under one variable of total well-being and simultaneously to have high levels of well-being under another variable. We can be rich but miserable, poor but happy and so on. Producing improvements in one variable of total well-being does not necessarily produce improvements in the other variables. Improvements in our physical well-being for example, do not necessarily produce improvements in social well-being. Likewise, although affluence is correlated with physical well-being, it is nonetheless possible to be rich and sick. The requirement of maximising several variables at once, as the WHO definition implies, is highly problematic.
On some occasions, the separate variables of total well-being will come into conflict, so that we cannot maximise one without sacrificing some level of another. For instance, it might be possible to achieve significant improvements in the population's physical well-being, but only if we are prepared to forgo much of the liberty we currently enjoy to choose our own lifestyles. If we could control people's diet and the amount and form of exercise they take, we might be able to reduce the incidence of many common diseases currently besetting affluent populations. However, since the freedom to choose the form of our own lives is one of the things that typically produce social and mental well-being, we would sacrifice some level of well-being under these two components of total well-being in order to maximise physical well-being. To achieve maximum levels of well-being across all the components of total well-being indicated in the WHO definition of health, our maximum levels of well-being would need to be very low indeed. The WHO's utopian vision for health could only be accomplished if "people ceased expecting much from life".  As a criterion for health, complete well-being simply asks too much.
The implausibility of identifying health with complete well-being is not the only problem. Also problematic is the specific inclusion of the criterion of social and mental well-being. While we might wish to acknowledge a relationship between these aspects of general well-being and the more specific condition of our physical well-being, nonetheless, their inclusion under the concept of health ultimately undermines any attempt to establish a plausible hierarchy of health needs while simultaneously expanding the realm of potential health needs to the point of unsustainability.
Several problems arise from the inclusion of mental well-being. There are no
doubt some conditions of mental functioning that we would want to include in
any definition of health, the absence of gross failures or severe disturbances
of cognitive functioning, for instance. Beyond this however, it is not obvious
how we are to proceed. In the first instance we are faced again with the
difficulty of interpretation. It is not clear how the WHO intends us to
understand the concept of 'mental well-being'. One might understand the concept
as referring to that aspect of mental functioning typically dealt with by
neurology, or psychology or we might take it that the concept of mental
well-being refers to the subjective state of happiness or perhaps some
combination of all three. Whichever way we interpret mental well-being, its
inclusion into the concept of health adds a still deeper layer of confusion to
what appears to be an already confused concept.
Alternatively, if we interpret mental well-being as referring to some psychological state we encounter another daunting array of difficulties. Psychological theories are themselves the focus of considerable controversy and at present, there is no agreed view on what constitutes mental illness much less what constitutes complete mental well-being. Szasz for instance, argues persuasively that many current psychological theories of mental well-being are little more than reflections of current social mores.  Certainly, many psychological theories seem to collapse into unacknowledged theories of subjective well-being. Candidates for a psychological theory of mental well-being include for instance, "the presence of democratic self-interest and ideals", the capacity to "develop realistic and satisfying roles and interpersonal relationships", and "well- adjustment".  If these characteristics are not ultimately reducible to an interpretation of subjective well-being, they are least highly problematic.
Finally, we may take a directly intuitive interpretation of the concept of mental well-being as subjective well-being, i.e., happiness, contentment and so on. Certainly the WHO's inclusion of mental well-being as a condition of health has been widely interpreted this way.  However, the consequences of including happiness under the definition of health verge on the absurd. There may be some individuals who are perpetually happy but such individuals are surely rare. More usually human beings suffer some quota of disappointment, dissatisfaction and general discontent. These causes of unhappiness permeate our lives to a greater or lesser extent since they are the expression of "infinite human desires constantly thwarted by the limitations of reality."  The WHO's inclusion of mental well-being would make these ordinary causes of unhappiness indicative of ill-health. Certainly unhappiness is often a consequence of disease but if happiness is an essential condition of health, then the human condition as such becomes pathologised. Most human beings will be, by definition, unhealthy for a much larger proportion of their lives than anyone previously imagined.
If happiness is an essential characteristic of health, the list of potential health needs will become as expansive as human desires. The provision of health care resources in this instance, would not only be directed towards maintaining some limited set of conditions associated with physical well-being but would also require the satisfaction of individuals' subjective preferences. Since there is virtually no limit to the range and type of preferences that individuals might have, there will be virtually no limit to the range and type of services that health systems would be required to provide. Although increasing utilization of health services is one of the major difficulties faced by current health systems, these problems would pale into insignificance if we were to accept the production of happiness as an appropriate goal for health care.
Disconcertingly, the inclusion of 'complete' mental well-being also seems to deprive us of the liberty of justified discontent. If we cannot be both unhappy and healthy then the discontented individual and the social reformer are simply 'sick'. The WHO definition would apparently make these individuals the appropriate subjects of medical treatment.  The incarceration of Soviet dissidents in psychiatric institutions provides an unfortunate example of this approach to identifying ill-health. To be discontent with an 'ideal' political system was to be by definition sick. Although it is doubtful that the founders of the WHO had such consequences in mind, such consequences are nonetheless inevitable. Including happiness into the concept of health shifts the concept of health into the realm of normative judgement. What may legitimately be described as a health need will depend on our view of the good and our view of the good will form a large part of what we judge as 'sick'. The inclusion of social wellbeing under the rubric of 'health' merely accentuates this problem. This would require us to resolve the question of what social arrangements are best before could we decide whether or not, someone is healthy.
While the inclusion of total well-being under the WHO definition of health is one of its attractions, it is also its greatest weaknesses. By including subjective well-being into the concept of health, the concept ultimately dissolves into a myriad personal subjectivities among which there is no obvious priority. Such theories have no precise content but rather become "vehicle[s] for changing human goals and expectations."  Rather than provide us with a limited set of needs upon which a distributive principle might operate, the WHO definition would allow health needs to expand to fill the entire compass of human desires. Anything and everything may ultimately be described as a health need. At the very least this seems to confuse appropriate spheres of responsibility. There is no reason to believe that health care professionals are particularly qualified to resolve issues of social organisation or human happiness. By attempting to include all aspects of life impinging on human well-being into the concept of health, the WHO definition ultimately becomes unintelligible.