The emergence of a modern paradigm for urban health

3.1 The legal recognition of health as a human right

The WHO Constitution (1948) marked the first international and legal articulation of a universal right to health. It advocated for ‘… the highest attainable standard of health as a fundamental right of every human being,’ a right that was subsequently embedded in many other international declarations. Developed in a succession of UN documents and commentaries, the right to health is highly nuanced and does not equate merely to provision of state health care services. In fact, the evolution of the modern concept of urban health has drawn on the definition of health embodied the WHO constitution, which states that:

This definition acknowledges that aspects of good health, whether at the level of people or populations, transcend a narrow medical perspective. For example, the UN Committee on Economic, Social, and Cultural Rights (2000) interprets the right to health as an inclusive right extending not only to timely and appropriate health care but also to the underlying determinants of health, including access to potable water and adequate sanitation, an adequate supply of safe food, nutrition and housing, and healthy occupational and environmental conditions, among other things. This wider framing has placed urban planning, management and development squarely at the centre of current and future efforts to secure health and wellbeing.

3.2 Urban health beyond the health sector; from treatment to prevention

One consequence of the framing of human health as broader than solely ‘the absence of disease or infirmity’ is that securing good health requires action beyond the health sector. The grounds for a non-medical approach to health were consolidated in the Alma Ata Declaration (WHO, 1978), which states that’the attainment of the highest possible level of health is a most important world-wide social goal whose realisation requires the action of many other social and economic sectors in addition to the health sector’.

Another significant conceptual advance supporting the need for urban health activity beyond health care is the place-based, or settings approach. The foundational document for the settings approach is the WHO Ottawa Charter (WHO, 1986), which recognised that ‘Health is created and lived by people within the settings of their everyday life; where they learn, work, play and love.’ In legitimizing this approach, the Ottawa Charter provided a strong framework to challenge the sometimes-dominant perception of healthcare systems as the sole (or primary) means for creating and sustaining health. Moreover, the Charter saw health as a ‘resource for everyday life’, not simply a final objective. The Ottawa Charter contained calls across several ‘areas for action’. Among those that were particularly innovative for the development of the concept of urban health, was the call for nations to create supportive environments; stipulating that protection of the natural and built environments and conservation of natural resources must be addressed in any health promotion strategy. Other areas of emphasis included; strengthening community action, building ‘Healthy Public Policy’, and recognizing that the responsibility for enabling, mediating, and advocating for health promotion lay with a variety of stakeholders including those outside the health sector. Coalescence of the ‘Healthy Public Policy’ concept can be found in Promoting Health through Public Policy (Milio, 1980 and 1986), supporting its key role in the Ottawa Charter. Healthy Public Policy advocates using the goal of positive health outcomes across all public policy areas. Its ambition is to create social and economic and environmental conditions for health at population level. As recent commentators note ‘Attention thus moves “upstream” to policies and institutions rather than “downstream” to behaviors or health services’ (Harris and Wise, 2020, p. 1).

More recently, we have seen the rise of the ‘Health in All Policies’ (HiAP) framework. HiAP as a moniker neatly captures the concept of Healthy Public Policy, giving it good policy traction. HiAP is also a developing approach to public policy that systematically accounts for the health implications of decisions in all sectors, seeks synergies, and avoids harmful health impacts to improve population health and health equity (Puska & Ståhl, 2010). It emphasises the importance of inter-sectoral work and policy coherence. HiAP relies heavily on the use of scientific evidence and evaluation tools, such as health impact assessments, which come in a wide variety of forms and may include testing of policy or project proposals, health economic assessment, and broad stakeholder input to inform the integration of health into a range of actions.

In broadening responsibility for health to non-health sectors there is an implied and sometimes explicit shift from curative to preventative approaches. For example, the Ottawa Charter articulates an ambition to ‘reorient health services’, stating that the health sector must move increasingly in the direction of health promotion, beyond clinical and treatment-based services. Public and urban health are now rising to this task, as they begin to embrace HiAP and health impact appraisal approaches that rely on processes less familiar to health practitioners, such as those for proposal and options testing for place-making, housing policy or urban infrastructure investment.

3.3 A growing emphasis on health equity

The 1978 Alma Ata Declaration also placed health equity firmly on the table: ‘The existing gross inequality in the health status of the people, particularly between developed and developing countries as well as within countries, is politically, socially, and economically unacceptable and is, therefore, of common concern to all countries.’

In 2005, WHO established the Commission on Social Determinants of Health to support countries and global health partners in addressing the social factors leading to ill health and health inequities. The Commission relied on several knowledge networks established to inform the report, including one which focused on urban issues. The Commission’s 2008 report and subsequent updates focus on improving daily living conditions, tackling the inequitable distribution of power, money, and resources; and better measuring and understanding the problem and assessing the impact of action.

Partly based on the evidence and analysis in the Commission’s report, health equity has achieved greater and greater resonance in urban health thinking—where it has become a vital strand weaving together a multitude of perspectives—and even within the broader development discourse. The reach of health equity and its core focus on supporting health globally across population groups can be seen in the ever-relevant report from the World Health Organization, Centre for Health Development, and the United Nations Human Settlements Programme ‘Hidden Cities: Unmasking and Overcoming Health Inequities in Urban Settings’ (WHO/UN, 2010). This in turn provided a platform for the foundational document of modern sustainable development ‘Transforming Our World: the 2030 Agenda for Sustainable Development’ (UN, 2015); advocating that ‘a rights-based approach to health requires that health policy and programmes prioritize the needs of those furthest behind first towards greater equity’.

On-the-ground research has also contributed to the policy shift toward a greater focus on health equity. For example, a series of field studies in the 1990s in Latin America and Africa changed the landscape for urban health by demonstrating the enormous disparities between the health status of urban populations living in the most deprived compared to the least deprived areas (Stephens et al., 1994; Stephens, 1996; McGranahan et al., 1999). These types of studies helped shift the focus from the urban poor, as an isolated and at-risk sub-population, to the broader issue of urban inequity in town and city governance. Moreover, the work of Wilkinson in ‘The Spirit Level’ (Pickett and Wilkinson, 2010) showed that large income inequalities can lead to a breakdown in social cohesion, with both direct and indirect negative consequences for physical and mental health and wider impacts across society.

3.4 Complexity and the ‘causes of the causes’ of ill-health

Growing understanding of what is now seen as a ‘web of causality’, along with experience in examining the process and outcomes of interventions that target the social and environmental determinants of health, have pushed the conceptual paradigm for urban health toward an embrace of complexity. The world is increasingly interconnected, complex. and uncertain, with significant implications for the way we generate, disseminate, and use knowledge.

Recognition of the role of urban complexity and the need for systemic approaches in research, policy development, and the design and practice of implementation is slowly spreading, from antecedents which span the last several decades. For example, in the 1990s, work on transport, health and environment articulated issues for cross-sectoral cooperation for health in public policy (Dora & Phillips, 2000). HiAP, too, implicitly recognizes the role of complexity in contemplating cross-sectoral synergies. From the early 2000s, the International Science Council (ISC) has promoted transdisciplinary science as a means of grasping and dealing with complexity when interacting with the major challenges facing humanity—including urban health. Moreover, the ISC programme on Urban Health and Wellbeing, founded in 2014, has focused strongly on systems thinking as a means for understanding and addressing urban health and wellbeing challenges (Gatzweiler, 2020; Gatzweiler et al., 2017, 2023).

In parallel, the ongoing work of the Stockholm Resilience Centre (e.g. Rockström et al., 2009; Richardson et al., 2023) to define and raise awareness of planetary boundaries and their possible impacts on health has stimulated several systemic urban health research programmes. These include the Wellcome Trust’s Our Planet Our Health funding initiative and many other national programmes for non-medical public health place-based research (e.g. Canada’s Healthy Cities CIHR funding, Australia’s HEAL NHMRC funding, UK’s NIHR’s Public Health Research programme and streams within the US’s NiH programmes). Through the networks of researchers and stakeholders involved in projects funded by these programmes, we are starting to see the creation of a more widespread contemporary understanding of urban health.

Not all innovation promoting a greater focus on complexity has come from the health side of the urban family: organizations that have brought attention to combined health and environmental issues in cities include city networks like Metropolis and Cities Alliance, civil society organizations like Slum Dwellers International, think tanks like IIED, and multilateral agencies like UN-Habitat, UNESCO, the OECD, and the World Bank. Intellectual work like Kate Raworth’s Doughnut Economics (2012) and other work on systems thinking (Puppim et al., 2015) has helped focus attention on the social origins of many environmental problems, helping to bridge the gaps between natural science assessments and potential applications in urban health, while signposting how integrated work on urban health needs to go beyond traditional urban planning.

The need to work on the upstream ‘causes of the causes’ of ill-health (Braveman and Gottlieb, 2014) is also gaining traction. For example, on how decision-taking in the built environment, housing, and construction sectors affects health (Pineo, 2022; Le Gouais et al., 2023), and on how approaches to financial risk, investment decisions and embedded culture in the development industry can influence health (Black et al., 2024). In parallel, new emphases are emerging on the Commercial (Gilmore et al., 2023) and Political Determinants of Health (Dawes and Gonzalez, 2023).

4.1 Healthy Cities movement and other city networks

One of the most important developments in the modern history of urban health is the WHO Healthy Cities movement. This built on novel undertakings in Canada in the 1980s, where the city of Toronto had declared its ambition to become a ‘Healthy City’. The developers of the Ottawa Charter had a strong intent to move from statements to demonstrable change, establishing settings-based networks and supporting a shift in focus, from specific ‘problems to be solved’ towards a systemic approach to urban health.the WHO European Regional Office supported the initiation of a small pilot programme, inviting European cities to commit to a set of values and approaches concordant with the Ottawa Charter, further developed in Promoting Health in the Urban Context (Duhl & Hancock, 1988). This approach was accessible, with a prescient action agenda, and dozens of cities expressed their interest, not just the handful that WHO expected. Interest and commitment quickly radiated to other regions, including Australia, New Zealand, and Japan, where networks of Healthy Cities emerged and were supported by city and national governments. Following the call to action from Toronto and inspired by the booming European network, provincial networks of Healthy Cities also emerged across Canada. Around the world, other local urban initiatives adopted the original Healthy Cities values in part or in whole. For example, Central and Latin American towns that had worked toward primary health care-focused ‘Sistemas Locales Para la Salud’ felt empowered to establish broader new networks for Healthy Cities and Communities (‘Ciudades y Comunidades de Salud’). Networks of healthy cities and towns also emerged in the Maghreb and Southern African regions. In this rapid spread, the central message of the Alma Alta Declaration, that achieving health required the action of many other sectors in addition to health, finally found fertile ground. Each of these individual and networked entities emphasized different priorities as locally relevant. In some contexts, basic sanitary and environmental health concerns were prioritised, in others, processes of equitable urbanization or the wellbeing of slum dwellers. Although difficult to assess, one estimate puts the number of ‘Healthy Cities’ styled initiatives at more than 15,000 (De Leeuw, 2017).

Comprehensive academic assessment and evaluation of healthy city initiatives is sparse. Due to the complexity of attempting to demonstrate causality, published analyses tend to dwell on qualitative aspects and description of process (de Leeuw et al., 2015). What is apparent is the diversity of such efforts and the importance of certain key elements (Harpham & Molyneux, 2001; Grant, 2015). Such elements include: the level of understanding and degree of political ‘sponsorship’, especially among city leaders; the empowerment of citizens and their understanding of how their quality of life is impacted by urban health challenges; and the existence of mechanisms whereby local health issues and concerns can influence local environments and urban policy.

The emergence of the Healthy Cities movement drew greater attention to urban health in global policy discourses. For example, in 1991, the World Health Assembly (the governing body of the World Health Organisation) adopted a resolution focused on health development in urban areas (WHO, 1991). In response to growing urban populations combined with increases in exposure to health risks, it urged Member States to strengthen their capacity for healthy urban development. Specific actions included: implementation of policies to foster sustainable urban development and preserve health-supporting environments; assessment of the impacts of all urban policies on community and environmental health; and creation of structures and processes for inter-sectoral and community participation in urban policy development.

The Healthy Cities movement represented one of the first global city networks; since then, many others have emerged with synergistic values and comparable packages of commitments. Such themed networks include WHO’s Age-Friendly Cities network, as well as Transition Towns, Child-Friendly Cities, Smart Cities, Sustainable Cities, Resilient Cities, and Slow Cities (de Leeuw, Simos & Forbat, 2020).

4.2 Bristol, Kobe, UN-Habitat and a joint focus on urban planning and spatial form

The WHO designates Collaborating Centres to support its city -based work. In 1990, the Institute of Action Research for Community Health in Indiana was the first Global Collaborating Center in Healthy Cities. The WHO Collaborating Centre for Research on Healthy Cities in Maastricht was designated in 1992. However, it was not until 1995, that the WHO European Regional Office established a unit centred on spatial form with expertise in urban planning and place-making through evidence-based design. This was the Collaborating Centre for Healthy Cities and Urban Policy in Bristol, UK, a centre unique in its placement within in a built environment faculty, rather than a health faculty. Its distinctive mission was to build bridges between the health and urban constituencies by involving planners, urban designers, geographers and landscape architects in the health agenda. As such, its focus was to act as a European and national hub to embed a deeper understanding of urban form as a determinant of health into public health understanding and practice. As a result of this work, the governance, planning and design of the physical form of cities became a new focus for the WHO European Healthy Cities Network during the 2000s, with the emergence of the concept of ‘Healthy Urban Planning’ (Barton and Tsourou, 2000). Urban planning went on to become a thematic priority during successive phases of the WHO Healthy Cities initiative. European member cities started to pilot and promote the use of ‘The Health Map’ (Figure 1) (Barton & Grant, 2006; Dahlgren & Whitehead, 1991), a tool developed at the Bristol Centre to enable cross-sector understanding and collaborative working on the determinants of urban health. There are now four versions of the health map to suit different applications. Having been translated into over 30 languages, the Health Map now been adopted by a wide range of actors at international, national and local level (Grant 2023).

Figure 1. The Health Map: The determinants of health seen through the lenses of agency in spatial planning, urban design, place management and city governance.

Also in 1995, WHO established the Centre for Health Development in Kobe, Japan (known as the Kobe Centre), a global research institution that quickly established a leadership role vis-à-vis the urban health agenda. An early symposium entitled ‘Urbanization: a global health challenge’ featured global experts in various sectors voicing support for inter-sectoral research in relation to complex health issues surrounding urbanization. The Kobe Centre was soon seen as a leader in promoting crosscutting research and new integrative approaches for analysing determinants of urban health (and for other pressing global health problems, like those of ageing societies). For example, in 2010, the Kobe Centre published the Urban Health Equity Assessment and Response Tool (Urban HEART), designed to help ministries of health and city-level health officials measure health inequities within and between cities. This tool has been applied in large metropolitan centres (populations over 1 million) in low- and middle-income countries around the world (Pakeman & Collins, 2018).

The preliminary activity at Kobe and Bristol thus laid the foundation for a stream of joint work on urban health involving the UN lead agencies for health and for urban settlements (WHO, 2010), much of this work focusing on the role of urban planning and spatial form.

Also in 2010, and in light of the continuing shift toward an eco-social rather than a biomedical view of health, there were two global landmark reports on urbanisation and health. The Kobe Centre co-produced a report on urbanisation and health with UN-Habitat. ‘Hidden Cities: Unmasking and Overcoming Health Inequities in Urban Settings’ (WHO/UN 2010a) sought to increase attention to urban health challenges, especially health inequities, by building a robust evidence base for action. In the same year, the final report from the ‘Global Research Network On Urban Health Equity’ provided an in-depth review of improving urban health equity through action on the social and environmental determinants of health, this included sections on urban planning and housing design (GRNUHE, 2010).

In 2016, the Kobe Centre and UN-Habitat co-produced a second major output, the ‘Global Report on Urban Health: Equitable healthier cities for Sustainable Development’ (WHO & UN-Habitat, 2016). This presented yet further evidence that in cities, health improvement depends not only on the strength of health systems, but also on shaping urban environments. Local governments typically have responsibility over many critical functions that determine liveability of cities such as land use planning, building standards, water and sanitation systems, roads and transportation, and environmental protection. Their actions can thus exacerbate or diminish health inequities. The report asserted that good governance for urban health demands a deliberately integrated approach across many different actors.

Also during 2016, the advent of the 3^rd vicennial United Nations Conference on Housing and Sustainable Urban Development (Habitat III) in Quito elevated the intensity of coordinated urban health activity between WHO and UN-Habitat. With a view to influencing the meeting’s outcomes, WHO published ‘Health as the Pulse of the New Urban Agenda’ (WHO, 2016) in collaboration with experts and in addition the International Science Council programme on Urban Health and Wellbeing; other global science groups like Future Earth contributed thinking on the role of systems approaches in achieving urban sustainability (Bai et al., 2016). These inputs fed decades of theory and lessons from practical experience in urban health into the Habitat III process and the New Urban Agenda, reflecting the ideas and insights of a diverse community of researchers and practitioners.

More recent products arising from this collaboration include health input to UN-Habitat’s ‘International Guidance for Urban and Territorial Planning’, which features guidance on how to use spatial planning to achieve better health outcomes (‘Integrating Health in Urban and Territorial Planning: a sourcebook’) (UN/WHO 2020) and a collection of case studies. Urban health continues to grow as a focus for both agencies.

4.3 Urban health work within WHO

Over its history, WHO has supported urban health through the work of its secretariat at global, regional, and country levels, providing technical guidance, supporting research, and advocating for action.

This has included technical guidance related to specific sectors, including active and sustainable transport (e.g., Health Economic Assessment Tool (HEAT¹); Integrated Sustainable Transport and Health Assessment Tool (iSThaT²), green space (e.g., Green Urban spaces and health tool (GreenUr³), energy (e.g., Clean Household Energy Solutions Toolkit (CHEST), housing (e.g., WHO Housing and health guidelines⁴), and many others. These instruments are widely used: for example, HEAT, which estimates health benefits from healthy transport interventions, has been used by hundreds of cities worldwide and was recently upgraded to include climate pollutants as well as health. There is also an extensive and growing compendium of WHO and other UN guidance on health and environment, with over 400 items. More broadly, WHO provides targeted technical support for urban health in areas ranging from air pollution, non-communicable diseases (NCDs) and injuries, emergency preparedness for Covid-19 and other disasters, vector control, and more.

WHO has also developed integrative implementation frameworks for urban health, like the Urban Health Initiative (UHI),⁵ which outlines a model process for integrating health into policymaking in the context of climate and air pollutants. Through such frameworks, it has also supported action research to estimate impacts of urban policies on a range of health impacts. For example, the UHI has applied Health Impact Assessment involving stakeholder and policy analyses to estimate expected co-benefits from sectoral policy alternatives to reduce air and climate pollutants in cities in low- and middle-income countries.

As discussed above, WHO has been instrumental in establishing major networks for urban health including Healthy Cities and Age-friendly Cities, and in supporting others like the Bloomberg Partnership for Healthy Cities. Through these networks and its own engagement, it has sought to mobilize urban health action—for example, through the BreatheLife ⁶ campaign which targets the implementation of city- and individual-level solutions for air pollution in support of global development goals.

In its 13^th General Programme of Work (2019-2023), WHO recognized the relevance of urban health to its programmes across the board, setting up a new cross-cutting urban health unit within the new Department of Social Determinants of Health (SDH). Important objectives of this unit include harnessing the momentum of global work on urban health and supporting countries and local communities to develop positive urbanization trajectories for health equity. Strategic advice from external experts was applied to frame the overall SDH agenda and the need for a focus on urban health was one key insight. This advisory recommendation was grounded in a perceived need to increase visibility, better align, coordinate, and build on existing urban health work across the organization.

The urban health unit has worked to consolidate a number of strands of urban health work, including by better defining and articulating the scope and possibilities of urban health and of a more strategic approach to these issues—this document is one element of that work. Another significant effort was the development of a global Urban Health Research Agenda for 2022-2032, which drew on an extensive scoping review, widespread consultation, and global and regional mapping of activities and stakeholders. More recently, the unit launched a new repository on urban health—a living resource covering urban planning, housing, environmental issues, transport and mobility, nutrition, physical activity, COVID-19, and many others. This searchable system allows users to access WHO materials by health topic category, product type, geographical area, and year of publication/development.⁷

Substantial work on urban health has also been undertaken in WHO’s regional and country offices. For example, in 2011, WHO’s Western Pacific Regional Office published Healthy urbanization: regional framework for scaling up and expanding healthy cities in the Western Pacific (WHO, 2011), which called for a systems-wide approach to urban health, recognizing the need for strong support from national governments (WHO, 2010). This action-oriented framework adopted the Kobe Centre’s definition for healthy urbanization as ‘the process of enabling people to gain greater control over their health and their determinants through good urban governance that creates equal social opportunities for health for all’ (WHO KOBE, 2008). With similar intent, the Pan American Health Organization recently launched a Healthy Municipalities, Cities, and Communities initiative to promote intersectorality, community participation, and an approach centred on health equity. As noted above, WHO’s European region has just celebrated 35 years of progress under its Healthy Cities Network initiative.

5.1 Urban health observatories

Given the significant health implications of urban environments and urbanization, cities and other urban health actors need detailed information on health needs and outcomes linked to demographic, economic, cultural, physical, and environmental data (WHO, 2023). Establishing effective mechanisms for monitoring urban health and health equity is essential (Caiaffa et al., 2014). Robust data, used wisely, can help integrate actions across existing systems in both health and non-health sectors (e.g., urban planning, urban resource and infrastructure investment, city development, transport, trade, food systems, etc.).

One approach to addressing the obstacles presented by the wide range of factors that influence health and the dispersed and uncoordinated nature of relevant data (Dias et al., 2015) is the ‘public health observatory’—or in urban settings, the ‘urban health observatory’ (UHO). However, the concept of health observatories dates back to the late 19th and early 20th centuries. Early efforts included the establishment of local health boards and the collection of vital statistics in cities like London, Liverpool and New York. The idea of health observatories gained momentum in the latter half of the 20th century, coinciding with advancements in epidemiology, data collection, and computing technologies. The focus on urban health observatories specifically emerged in the late 20th and early 21st centuries, driven by increasing urbanization and the recognition that cities face unique health challenges.

Key milestones include: WHO support in 1998, through launching the Health Metrics Network to improve health information systems globally; the European Urban Health Observatory (EURO-URHO), established in the early 2000s. In 2006, UN-Habitat reported the existence of 119 local urban observatories, its Global Urban Observatory Unit oversees and coordinates approximately 374 today and focuses on monitoring urban conditions and trends, including health indicators, to support sustainable urban development.

In recent years, the rise of big data, advanced analytics, and geographic information systems has further enhanced the capabilities of urban health observatories. They now integrate diverse data sources, including electronic health records, environmental data, and social determinants of health, to provide a comprehensive view of urban health. By 2010, urban health observatories had been established in every inhabited continent, countries hosting one (or more) included the UK, Spain, France, Canada, USA, Brazil, Chile, South Africa, Kenya, India, China and Australia. A decade ago, the Asia-Pacific Urban Observatory Network and Africa Centre for Disease Control and Prevention Health Observatory were also established.