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The current WHO definition of health, formulated in 1948, describes health as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.”1 At that time this formulation was groundbreaking because of its breadth and ambition. It overcame the negative definition of health as absence of disease and included the physical, mental, and social domains. Although the definition has been criticised over the past 60 years, it has never been adapted. Criticism is now intensifying,2-5 and as populations age and the pattern of illnesses changes the definition may even be counterproductive. The paper summarises the limitations of the WHO definition and describes the proposals for making it more useful that were developed at a conference of international health experts held in the Netherlands.6
How should we define health?
The WHO definition of health as complete wellbeing is no longer fit for purpose given the rise of
chronic disease. Machteld Huber and colleagues propose changing the emphasis towards the
ability to adapt and self manage in the face of social, physical, and emotional challenges
Machteld Huber senior researcher1, J André Knottnerus president, Scientific Council for Government
Policy 2, Lawrence Green editor in chief, Oxford Bibliographies Online—public health 3, Henriëtte
van der Horst head 4, Alejandro R Jadad professor5, Daan Kromhout vice president, Health Council
of the Netherlands 6, Brian Leonard professor 7, Kate Lorig professor 8, Maria Isabel Loureiro
coordinator for health promotion and protection9, Jos W M van der Meer professor10, Paul Schnabel
director 11, Richard Smith director 12, Chris van Weel head 13, Henk Smid director 14
1Louis Bolk Institute, Department of Healthcare and Nutrition, Hoofdstraat 24, NL-3972 LA Driebergen, Netherlands; 2Department of General Practice,
Maastricht University, Scientific Council for Government Policy, Postbus 20004, NL-2500 EA The Hague, Netherlands;3Department of Epidemiology
and Biostatistics, School of Medicine, University of California at San Francisco, USA; 4Department of General Practice, VU Medical Center,
Amsterdam, Netherlands; 5Centre for Global eHealth Innovation, Toronto General Hospital, Toronto, Canada; 6Department of Public Health Research,
Wageningen University, The Hague, Netherlands; 7Pharmacology Department, National University of Ireland, Galway, Ireland; 8Stanford Patient
Education Research Center, Palo Alto, CA, USA; 9National School of Public Health/New University of Lisbon, Portugal; 10General Internal Medicine,
Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands; 11Netherlands Institute for Social Research, The Hague, Netherlands;
12UnitedHealth Chronic Disease Initiative, London, UK; 13Department of Primary and Community Care, Radboud University Nijmegen Medical
Centre; 14Netherlands Organisation for Health Research and Development, The Hague, Netherlands
The current WHO definition of health, formulated in 1948,
describes health as “a state of complete physical, mental and
social well-being and not merely the absence of disease or
infirmity.”1At that time this formulation was groundbreaking
because of its breadth and ambition. It overcame the negative
definition of health as absence of disease and included the
physical, mental, and social domains. Although the definition
has been criticised over the past 60 years, it has never been
adapted. Criticism is now intensifying,2-5 and as populations age
and the pattern of illnesses changes the definition may even be
counterproductive. The paper summarises the limitations of the
WHO definition and describes the proposals for making it more
useful that were developed at a conference of international health
experts held in the Netherlands.6
Limitations of WHO definition
Most criticism of the WHO definition concerns the absoluteness
of the word “complete” in relation to wellbeing. The first
problem is that it unintentionally contributes to the
medicalisation of society. The requirement for complete health
“would leave most of us unhealthy most of the time.”4It
therefore supports the tendencies of the medical technology and
drug industries, in association with professional organisations,
to redefine diseases, expanding the scope of the healthcare
system. New screening technologies detect abnormalities at
levels that might never cause illness and pharmaceutical
companies produce drugs for “conditions” not previously
defined as health problems. Thresholds for intervention tend to
be lowered—for example, with blood pressure, lipids, and sugar.
The persistent emphasis on complete physical wellbeing could
lead to large groups of people becoming eligible for screening
or for expensive interventions even when only one person might
benefit, and it might result in higher levels of medical
dependency and risk.
The second problem is that since 1948 the demography of
populations and the nature of disease have changed considerably.
In 1948 acute diseases presented the main burden of illness and
chronic diseases led to early death. In that context WHO
articulated a helpful ambition. Disease patterns have changed,
with public health measures such as improved nutrition, hygiene,
and sanitation and more powerful healthcare interventions. The
number of people living with chronic diseases for decades is
increasing worldwide; even in the slums of India the mortality
pattern is increasingly burdened by chronic diseases.7
Ageing with chronic illnesses has become the norm, and chronic
diseases account for most of the expenditures of the healthcare
system, putting pressure on its sustainability. In this context the
Correspondence to: M Huber
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WHO definition becomes counterproductive as it declares people
with chronic diseases and disabilities definitively ill. It
minimises the role of the human capacity to cope autonomously
with life’s ever changing physical, emotional, and social
challenges and to function with fulfilment and a feeling of
wellbeing with a chronic disease or disability.
The third problem is the operationalisation of the definition.
WHO has developed several systems to classify diseases and
describe aspects of health, disability, functioning, and quality
of life. Yet because of the reference to a complete state, the
definition remains “impracticable, because ‘complete’ is neither
operational nor measurable.”3 4
Need for reformulation
Various proposals have been made for adapting the definition
of health. The best known is the Ottawa Charter,8which
emphasises social and personal resources as well as physical
capacity. However, WHO has taken up none of these proposals.
Nevertheless, the limitations of the current definition are
increasingly affecting health policy. For example, in prevention
programmes and healthcare the definition of health determines
the outcome measures: health gain in survival years may be less
relevant than societal participation, and an increase in coping
capacity may be more relevant and realistic than complete
Redefining health is an ambitious and complex goal; many
aspects need to be considered, many stakeholders consulted,
and many cultures reflected, and it must also take into account
future scientific and technological advances. The discussion of
experts at the Dutch conference, however, led to broad support
for moving from the present static formulation towards a more
dynamic one based on the resilience or capacity to cope and
maintain and restore one’s integrity, equilibrium, and sense of
wellbeing.6The preferred view on health was “the ability to
adapt and to self manage.”
Participants questioned whether a new formulation should be
called a definition, because this implied set boundaries and
trying to arrive at a precise meaning. They preferred that the
definition should be replaced by a concept or conceptual
framework of health. A general concept, according to sociologist
Blumer,9represents a characterisation of a generally agreed
direction in which to look, as reference. But operational
definitions are also needed for practical life such as measurement
The first step towards using the concept of “health, as the ability
to adapt and to self manage” is to identify and characterise it
for the three domains of health: physical, mental, and social.
The following examples attempt to illustrate this.
Physical health
In the physical domain a healthy organism is capable of
“allostasis”—the maintenance of physiological homoeostasis
through changing circumstances.10 When confronted with
physiological stress, a healthy organism is able to mount a
protective response, to reduce the potential for harm, and restore
an (adapted) equilibrium. If this physiological coping strategy
is not successful, damage (or “allostatic load”) remains, which
may finally result in illness.11
Mental health
In the mental domain Antonovsky describes the “sense of
coherence” as a factor that contributes to a successful capacity
to cope, recover from strong psychological stress, and prevent
post-traumatic stress disorders.12 13 The sense of coherence
includes the subjective faculties enhancing the
comprehensibility, manageability, and meaningfulness of a
difficult situation. A strengthened capability to adapt and to
manage yourself often improves subjective wellbeing and may
result in a positive interaction between mind and body—for
example, patients with chronic fatigue syndrome treated with
cognitive behavioural therapy reported positive effects on
symptoms and wellbeing. This was accompanied by an increase
in brain grey matter volume, although the causal relation and
direction of this association are still unclear.14
Social health
Several dimensions of health can be identified in the social
domain, including people’s capacity to fulfil their potential and
obligations, the ability to manage their life with some degree
of independence despite a medical condition, and the ability to
participate in social activities including work. Health in this
domain can be regarded as a dynamic balance between
opportunities and limitations, shifting through life and affected
by external conditions such as social and environmental
challenges. By successfully adapting to an illness, people are
able to work or to participate in social activities and feel healthy
despite limitations. This is shown in evaluations of the Stanford
chronic disease self management programme: extensively
monitored patients with chronic illnesses, who learnt to manage
their life better and to cope with their disease, reported improved
self rated health, less distress, less fatigue, more energy, and
fewer perceived disabilities and limitations in social activities
after the training. Healthcare costs also fell.15 16
If people are able to develop successful strategies for coping,
(age related) impaired functioning does not strongly change the
perceived quality of life, a phenomenon known as the disability
Measuring health
The general concept of health is useful for management and
policies, and it can also support doctors in their daily
communication with patients because it focuses on
empowerment of the patient (for example, by changing a
lifestyle), which the doctor can explain instead of just removing
symptoms by a drug. However, operational definitions are
needed for measurement purposes, research, and evaluating
Measurement might be helped by constructing health frames
that systematise different operational needs—for example,
differentiating between the health status of individuals and
populations and between objective and subjective indicators of
health. The measurement instruments should relate to health as
the ability to adapt and to self manage. Good first operational
tools include the existing methods for assessing functional status
and measuring quality of life and sense of wellbeing. WHO has
developed several classification systems measuring gradations
of health.18 These assess aspects like disability, functioning, and
perceived quality of life and wellbeing.
In primary care, the Dartmouth Cooperative Group
(COOP)/Wonca (the world organisation of family doctors)
assessment of functional status, validated for different social
and cultural settings, has been developed to obtain insight into
the perceived health of individuals. The COOP/Wonca
Functional Health Assessment Charts present six different
dimensions of health, each supported by cartoon-like
drawings.19 20 Each measures the ability to perform daily life
activities on a 1 to 5 scale.
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Such instruments offer valuable information about a variety of
aspects, from functioning to the experienced quality of life. Yet
there are few instruments for measuring aspects of health like
the individual’s capacity to cope and to adapt, or to measure the
strength of a person’s physiological resilience. A new
formulation about health could stimulate research on this.
Just as environmental scientists describe the health of the earth
as the capacity of a complex system to maintain a stable
environment within a relatively narrow range,21 we propose the
formulation of health as the ability to adapt and to self manage.
This could be a starting point for a similarly fresh, 21st century
way of conceptualising human health with a set of dynamic
features and dimensions that can be measured. Discussion about
this should continue and involve other stakeholders, including
patients and lay members of the public.
We thank Jennie Popay, Atie Schipaanboord, Eert Schoten, and Rudy
Westendorp for their thoughts.
Contributors and sources: This paper builds on a two day invitational
conference in the Netherlands on defining health, organised by the
Health Council of the Netherlands (Gezondheidsraad) and the
Netherlands Organisation for Health Research and Development
(ZonMw). At the conference a multidisciplinary group of 38 international
experts discussed the topic and were guided by a review of the literature.
MH organised the conference and drafted the report and this article.
LG, HvdH, ARJ, DK, BL, KL, MIL, JvdM, PS, RS, and CvW contributed
as speakers. HS hosted the conference with JAK, who chaired it. All
authors contributed to the article. JAK is guarantor.
Competing interests: All authors have completed the ICJME unified
disclosure form at (available on
request from the corresponding author) and declare no support from
any organisation for the submitted work; no financial relationships with
any organisation that might have an interest in the submitted work in
the previous three years; and no other relationships or activities that
could appear to have influenced the submitted work.
Provenance and peer review: Not commissioned; externally peer
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Accepted: 15 June 2011
Cite this as: BMJ 2011;343:d4163
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Individual differences in the aging process can be conceptualized as an accumulation of wear and tear of daily experiences and major life stressors that interact with the genetic constitution and predisposing early life experiences. The neuroendocrine system, autonomic nervous system, and immune system are mediators of adaptation to challenges of daily life, referred to as allostasis, meaning "maintaining stability through change." Physiological mediators such as adrenalin from the adrenal medulla, glucocorticoids from the adrenal cortex, and cytokines from cells of the immune system act upon receptors in various tissues and organs to produce effects that are adaptive in the short run but can be damaging if the mediators are not shut off when no longer needed. When release of the mediators is not efficiently terminated, their effects on target cells are prolonged, leading to other consequences that may include receptor desensitization and tissue damage. This process has been named "allostatic load," and it refers to the price the tissue or organ pays for an overactive or inefficiently managed allostatic response. Therefore, allostatic load refers to the "cost" of adaptation. This article discusses the mediators of allostasis and their contributions to allostatic load as well as their role in resilience of the aging organism to stressful experiences.