Environment and Health – a consensus-based partnership
Until the beginning of the 20th century, urban planning and public health professionals worked side-by-side to improve the living conditions of the population, particularly in mitigating the harmful effects of urbanization and industrialization processes on population health. However, changes in the epidemiological paradigm, from environmental theories to germ theories, which gave greater importance to laboratory research in combating health problems, and the emergence of a new model of territorial organization that favored a specialization of urban land use, distanced the two disciplines.
Currently, we are witnessing a progressive (re)valuation of environmental factors (social and built environment), and it is generally agreed in the scientific community that the environment where an individual lives, travels, and works can determine their health by shaping their behaviors and habits of physical activity and diet, among other aspects. However, the mechanisms underlying the association between the neighborhood environment and the body composition of individuals are tenuous and subtle.
It is known that individuals living in urban environments that prioritize people over cars have better health indicators. It is also known that urban environments planned with an emphasis on car traffic and without green spaces create feelings of greater insecurity and stress in their residents. These feelings are associated with biological responses that trigger mechanisms that include the release of hormones (noradrenaline, cortisol, etc.) that have direct and indirect effects on health, particularly on diseases such as depression, diabetes and obesity (3).
In an attempt to quantify the association between environment and body composition, the concept of "obesogenic environment" emerged in the late 1990s, evaluating a territory according to its capacity to promote weight gain in individuals. An obesogenic environment combines two aspects simultaneously: the existence of places selling high-calorie food and the lack of elements that allow individuals to walk and be physically active, i.e., places that promote the use of cars. However, the results of studies on "obesogenic environments" in various European countries are inconclusive and sometimes even contrary to expectations. This is because defining the territory using only these aspects is quite reductive and does not reflect the true essence of the places.
Definition and measurement of the Environment/Territory
In Geography, territory is characterized by the inseparability and interdependence of material, physical, and social aspects resulting from human action. In this sense, territory is composed of geographical, anthropological, cultural, social, economic, bioecological, etc., dimensions simultaneously. It is due to this multidimensionality that its measurement, evaluation, and interpretation become an extremely complex task. Regardless, the need to understand how health phenomena, such as the prevalence of obesity, are spatially distributed and why, persists. Therefore, "composite indices" are developed that, using data from different sources and natures (census data, land use data, among others), attempt to represent each territorial unit through endogenous and exogenous factors and their interaction. These composite indicators are used in several countries to identify areas with greater social and material deprivation and, consequently, areas for priority intervention.
In a study on the municipality of Lisbon, aimed at evaluating the impact of the environment on childhood obesity, a composite index, designated as the multidimensional environmental index, was developed using 20 social indicators and 14 indicators of the built environment. This index revealed that there is a higher proportion of overweight and obese children in areas of the city with low socioeconomic levels, and that more advantageous environments (with high socioeconomic levels and buildings with parking and larger houses) appear to protect children from obesity.
Another study, also in the municipality of Lisbon but focused solely on aspects of the built environment, used 62 indicators to construct a composite index. The results of this study showed that areas with newer buildings, parking, and more green spaces appear to protect children from obesity, even when considering the socioeconomic status of the family and the weight of mothers (factors widely known as determinants of children's weight). This is the type of information that contributes to healthy urban planning, a responsibility that lies with local government bodies.
Healthy urban planning in the fight against childhood obesity
According to the latest evidence, local authorities are the most qualified entities to lead and coordinate interventions to prevent childhood obesity. This is because they are close to the population, possess privileged knowledge of their territory and its needs, and are able to act in a multi-sectoral and multi-level manner. Therefore, in 2008, the Healthy Towns, involving 9 local authorities, with the specific objective of evaluating environmental approaches to obesity prevention. This program explored the role of urban planning professionals in interventions to combat obesity. It also revealed that it is necessary to align health and urban planning policies to ensure the articulation of the two sectors in pursuit of common goals, and that, to combat obesity from an environmental perspective, it is necessary to create a common language and close cooperation between planning and health professionals.
has existed for over 20 years, Portuguese Network of Healthy Municipalities encouraging municipalities to make health a central issue in their actions. The network's main objectives are to promote health for all through participation in the debate on national health policies, and to support interventions that promote health at the local level by ensuring community involvement, among other aspects.
However, only 57 of the 308 Portuguese municipalities are members of the Portuguese Network of Healthy Municipalities. And of those 57 members, only a small number of municipalities promote interventions to combat childhood obesity. The scarcity of municipal projects to combat one of the most serious public health problems of our time highlights a disconnect between national health policies and the priorities and actions of local government.
It is necessary for local authorities to follow the example of the central government and make the fight against childhood obesity a priority. Furthermore, a parallel must be established between national programs promoting healthy diets and physical activity and local interventions coordinated by local authorities. This requires, among other aspects, greater empowerment of urban planning professionals to focus their actions on health and, above all, multidisciplinary work in the development of multisectoral and sustainable interventions.
