[This article was published in Catalan in Espai Salut, a bulletin published by the Diputació de Barcelona]
The older population is growing rapidly. In 2017, the world counted 962 million adults aged 60 or over, and this number is expected to double to 2.1 billion by 2050. The ageing of the population calls for measures that help prevent or reduce disease and disability among older adults and keep the older population healthy longer. A concept to describe this is healthy ageing, which is defined by the World Health Organization (WHO) as “the process of developing and maintaining the functional ability that enables wellbeing in older age”.
The ageing of the population calls for measures that help prevent or reduce disease and disability among older adults and keep the older population healthy longer
Older adults’ wellbeing is strongly linked to the residential environment, where the older population generally spends more time than the younger population due to, for instance, retirement or increasingly limited mobility. An important factor in the association with health is the neighbourhood’s built environment, which can either facilitate or hinder participation in activities and healthy behaviour. For instance, walk-friendly infrastructures and access to destinations and services have been found to be positively related with higher physical activity and walking among older adults.
Available scientific evidence
One feature of the build environment that has received increasing attention over the last years is green space. Green spaces are areas partially or fully covered by vegetation (e.g. trees, grass, and bushes), which can come in many forms, including large forests, small city parks, and even the street trees in your neighbourhood. Recent studies have found that living in neighbourhoods with more green space is associated with improved mental health and self-perceived physical health, reduced levels of obesity, and reduced risk of disease. As older adults generally are more bound to their direct home surroundings, they may especially benefit from green spaces in the neighbourhood.
Older adults’ wellbeing is strongly linked to the residential environment, where the older population generally spends more time than the younger population due to, for instance, retirement or increasingly limited mobility
Though studies on the older population are limited, exposure to green spaces has been associated with various health outcomes. Older adults living in neighbourhoods with more green space have reported to have a better general health, more life satisfaction, and less stress. In addition, higher exposure to green space has been associated with a lower risk of cardiovascular disease such as diabetes. Moreover, more green space in the neighbourhood and more visits to green spaces have been associated with lower mortality in the older population.
While these studies focused on the older population, studies on determinants of healthy ageing are very scarce. One of the most important determinants of healthy ageing is cognitive functioning, which includes abilities as reasoning, short-term memory, and verbal fluency. Cognitive functioning generally declines as you age. In a recent study led by the Barcelona Institute for Global Health (ISGlobal) with data of over 5,600 British civil servants, we found that those living in neighbourhoods with more green space had a slower cognitive decline over the study period.
Another important determinant of healthy ageing is physical functioning. Physical functioning, or physical capacity, refers to the capacities of the body that are needed to do basic activities in daily life such as walking, balance, and strength. Similarly to our previous study, we found that the British civil servants who were living in greener neighbourhoods and living closer to a green space had a slower decline in walking speed.
How does green space benefit health?
Several pathways through which green space may benefit health have been proposed. Some of these pathways may be especially relevant for the older population. Neighbourhoods with higher levels of green space have been found to foster social cohesion and reduce feelings of loneliness, which are very relevant predictors of health in the older population. Additionally, access to more green space in the neighbourhood may provide incentive for doing more physical activity. Staying physically active is important for health at older age. Furthermore, green spaces may reduce exposure to harmful factors as noise, air pollution, and heat to which the older population may be especially vulnerable.
Green spaces may reduce exposure to harmful factors as noise, air pollution, and heat to which the older population may be especially vulnerable
However, for a green space to benefit health, we need to consider the quality and design of the green space that should be adapted to the demography of the residents of the neighbourhood. For older adults, features such as benches and walkable paths may be especially important. Moreover, we should pay special attention to accessibility to ensure that green spaces can be reached by all population groups. For older adults to move around, we need to consider the walkability and safety of the streets around the green space and access to public transport. Thus, for a good quality green space to benefit health, we should look beyond the green space itself, but also to its integration in the city.
Despite the health benefits of green spaces, they are not the only factor of urban life that determine the “age-friendliness” of a city. The WHO has identified eight domains of urban life related to “age-friendliness”: outdoor spaces and buildings; transportation; housing; social participation; respect and social inclusion; civic participation and employment; communication and information; and community support and health services.
To conclude, the integration of well-designed and maintained green spaces can help the creation of age-friendly cities and is a promising and needed public health intervention.