Green space as a buffer between stressful life events and health☆
Introduction
Many people seek out nature in times of stress. For example, following the attacks on the World Trade Centre in 2001, managers of national parks observed a pronounced increase in the number of visits. In an interview published on the Environment News Service, one manager remarked, “People were going out that day, going for walks, reflecting on what was going on” (Lazaroff, 2002). Such nature-based coping strategies appear to be effective, as evidenced by a growing number of studies showing that contact with nature can have beneficial health effects (De Vries et al., 2003, Maas et al., 2006, Mitchell and Popham, 2007). Controlled, experimental research has found especially strong evidence for a positive relation between exposure to nature and restoration from stress and attention fatigue (Hartig et al., 2003, Ulrich et al., 1991).
Unfortunately, due to increasing urbanization, combined with spatial planning policies of densification, modern people's homes have become more and more removed from green environments. According to dynamic stress-vulnerability (DSV) models (Heady and Wearing, 1989, Ormel and Neeleman, 2000), restricted access to green space may increase people's vulnerability to the impact of stressful life events on mental and physical health. In general, individuals living in areas that lack green space may be more vulnerable to the negative impacts of stressful life events because they have less opportunities for nature-based coping strategies than individuals living in areas with abundant green space (Kaplan & Kaplan, 1989). Thus, the availability of green space in the living environment may be an important environmental factor that moderates the relationship between stressful life events and health.
The aim of the present study was to investigate to what extent the presence of green space can buffer adverse health impacts of stressful life events. In the following paragraphs, we first discuss the importance of neighbourhood characteristics for well-being, and the increasing recognition of green space as a valuable neighbourhood resource. Next, we review theoretical and empirical research on restorative effects of green space. We also consider evidence for buffering effects of green space. Finally, we present and discuss the results of a large-scale study that examined moderating effects of green space nearby and farther away from the home on relationships between stressful life events and self-reported physical, mental, and general health.
There is a long tradition of research exploring the relationship between neighbourhood characteristics and individual well-being (Macintyre & Ellaway, 2000). Traditionally, this research has focused mostly on sociological and psychosocial factors such as social cohesion, social capital and sense of community (Gee & Payne-Sturges, 2004). However, there is growing recognition for the importance of physical neighbourhood circumstances as both sources of stress and as resources that can help residents to cope with stress (Diez-Roux, 1998). One physical characteristic that has recently received much attention from researchers and policy makers as a potentially powerful physical neighbourhood resource is green space.
Findings from recent EU research programs on urban green spaces confirm their role in improving people's life quality (De Ridder, 2003). Like other public areas, parks and other green spaces can support physical activity and facilitate social cohesion (Kaczynski and Henderson, 2007, Maas et al., 2008). However, green spaces appear to have a special quality that is lacking in other public areas: contact with green space can provide restoration from stress and mental fatigue. This so-called ‘restorative quality’ of nature is corroborated by results of national surveys in several countries, which have consistently shown that people consider contact with nature one of the most powerful ways to obtain relief from stress (Grahn & Stigsdotter, 2003).
Restorative effects of green space have generally been explained from an evolutionary perspective. Most of these explanations have in common the argument that, as a remnant of two or three million years of evolution in natural environments, modern humans have developed a partly genetic readiness to respond positively to habitable settings that were favourable to well-being and survival for pre-modern people (Kellert & Wilson, 1993). Notably, this readiness to respond positively to habitable settings is assumed to be triggered only by natural environments, humans do not possess such a disposition for most built environments and materials (Ulrich, 1993).
An important implication of people's readiness to respond positively to nature is that their attention is easily and almost effortlessly held by natural scenes. This attention-drawing quality of natural settings is referred to as ‘soft fascination’ (Kaplan & Kaplan, 1989). Soft fascination is assumed to play an important role in the restorative quality of nature. When nature captures people's attention, executive systems that regulate directed attention get to rest, pessimistic thoughts are blocked, and negative emotions are replaced by positive ones (Parsons, 1991). Prolonged exposure to high-quality natural settings may even stimulate reflections on life's larger questions such as one's priorities, goals, and one's place in the larger scheme of things (Mayer, Frantz, Bruehlman-Senecal, & Dolliver, 2009). This may help a person to find new sense and direction in life.
A small but growing body of well-controlled empirical research speaks directly to the restorative effects of green space (Health Council of the Netherlands, 2004, Van den Berg et al., 2007). In general, this research has shown more positive affective, cognitive, and physiological responses to natural settings as compared to built settings. These positive responses have been observed in diverse settings including remote wilderness areas (Hartig, Mang, & Evans, 1991) as well as nearby green space such as gardens (Ottosson & Grahn, 2005). Notably, people need not go outdoors to profit from nature's restorative functions. Merely viewing green space through a window can already have restorative effects (Faber Taylor, Kuo, & Sullivan, 2002).
The findings of field studies are backed up by laboratory experiments in which stressed participants are randomly assigned to conditions of viewing visual simulations of natural and urban environments (e.g. Berto, 2005, Ulrich et al., 1991, Van den Berg et al., 2003). These experiments have consistently shown that viewing slides or videos of natural environments leads to a faster and more complete stress recovery than viewing built environments. In sum, there is convergent evidence from different lines of research that contact with real or simulated natural environments can provide restoration from stress and mental fatigue.
Green space may not only affect stress and mental fatigue directly, but may also have indirect effects by serving as a buffer against the health impacts of stressful life events. A buffer is a moderating variable that decreases the association between a negative independent variable and a negative outcome variable, explaining how or under what circumstances the independent variable affects the outcome variable (cf. Baron & Kenny, 1986). As graphically illustrated in Fig. 1, buffering effects are indicated by the interaction of the independent variable and hypothesized moderator variable in explaining the outcome variable. There may also be significant main effects for the predictor and the moderator, but these are not directly relevant conceptually to testing the buffering hypothesis (Baron & Kenny, 1986, p. 1174).
A few studies have explicitly examined buffering effects of green space on various outcome variables. For example, research in rural communities in New York showed that nature in the residential environment may serve as a buffer for the impact of stressful life events on rural children's psychological well-being (Wells & Evans, 2003). The impact of stressful life events on psychological distress and self-worth was weaker among children with a large amount of nature in or around their house than among children with a small amount of nearby nature. A study among employees of a Southern European company found that a view of natural elements (i.e., trees, vegetation, plants, and foliage) buffered the negative impact of job stress on intention to quit and general well-being (Leather, Pyrgas, Beale, & Lawrence, 1998). An experimental study showed that exposure to nature-dominated roadside views, as compared to artefact-dominated views, decreased the magnitude of the galvanic skin response to a consequent stressor (Parsons, Tassinary, Ulrich, Hebl, & Grossman-Alexander, 1998). A recent Swedish study found that the influence of a “personal crisis” (i.e., a difficult event or severe loss with a strong emotional impact) on self-reported mental health and attention was weaker among individuals who spent much time contemplating nature and wildlife (Ottosson & Grahn, 2008).
Other studies have investigated protective effects of contact with nature among individuals who are undergoing stressful life events. For example, an intervention study among women diagnosed with breast cancer showed that women who engaged in nature-based activities on a daily basis showed greater improvement in performance on attention tasks than a nonintervention group (Cimprich & Ronis, 2003). A Swedish study among residents of high-noise neighbourhoods found that residents with “better” availability of green areas exhibited less stress-related psychosocial symptoms than residents with “poorer” availability of green areas (Gidlöf-Gunnarsson & Öhrström, 2007). Because the latter studies did not include unstressed control groups, they do not provide direct evidence for buffering effects of green space. Nevertheless, they are consistent with the idea that contact with nature can help individuals to better cope with stressful life events.
Research on the buffering effects of green space has mostly relied on psycho-physiological and cognitive stress measures as outcome variables. Although some studies have used measures of general well-being or mental health (e.g. Leather et al., 1998, Ottosson and Grahn, 2008, Wells and Evans, 2003), the ability of green space to protect people against the impact of stressors on physical health indicators has not yet received much attention. Theoretically, however, green space could be highly relevant to buffering physical health outcomes. Research has shown that stressful life events may lead to a sudden onset or worsening of different physical illnesses, depending on many moderating factors, including environmental resources (Tosevski & Milovancevic, 2006). Thus, buffering effects of green space may not only become manifest in decreased symptoms of stress, but also in better physical health.
To date, research on the buffering effects of green space has mostly focused on readily available green space in the close vicinity of the home or workplace, e.g. plants in the living room or grass in the yard (Wells & Evans, 2003), a view of nature from the window (Leather et al., 1998, Parsons et al., 1998), or green areas “close to your dwelling” (Gidlöf-Gunnarsson & Öhrström, 2007). The results confirm that green space “on one's doorstep” can serve as a buffer against stress. Indeed, as Rachel Kaplan has put it, “accumulating from many short episodes, the view from the window can provide long-term contact with the natural environment. Perhaps such an enduring connection is particularly useful for sustaining restoration” (Kaplan, 2001, p. 540).
In times of stress, however, possibilities for contact with more large-scale areas of nature farther away from one's home may be equally, or perhaps even more important for staying healthy. When people are confronted with major life events, such as death or divorce, they need time to reflect on their life, their actions, and priorities, to cope with the events. Such reflection involves a deep level of restoration (Kaplan & Kaplan, 1989, p. 197). To be sure, such deep restoration is possible in nearby green space (think of a person contemplating fish in a garden pond). However, it is presumably more easily obtained in more extensive natural areas farther away from one's home, where one can more readily obtain a sense of being away and connection with nature. A survey about the choice of restorative settings among elementary school teachers in Chicago provides some support for the validity of these notions (Gulwadi, 2006). Teachers who frequently suffered from job stress preferred to actually go out into nature and stay away for a longer period of time (such as taking a walk in the woods), whereas teachers with low levels of job stress found sufficient merit in brief sensory enjoyment of nearby nature (such as listening to birds' chirping). Thus, the availability of more large-scale natural settings at a somewhat farther distance from home may become more important in times of severe stress or crisis. As yet, however, health buffering effects of green space have not yet been related to the distance of the green space from home.
In the present study, we used quantitative data of a representative sample of Dutch residents to investigate to what extent the presence of green space in the living environment can buffer the adverse impacts of stressful life events on perceived health. In contrast to previous studies, we not only measured mental health, but also physical and perceived general health. To gain more insight into the importance of the distance to green space, we distinguished between green space within a 1-km radius around the home, and green space within a 3-km radius. Our main hypothesis was that the adverse impacts of experiencing stressful life events on physical, mental, and general health is less severe in living environments with more green space, because green space can reduce vulnerability and thus promote resilience against stress. We also hypothesized that buffering effects would be stronger for green space in a 3-km radius than for green space in a 1-km radius, because having larger areas of green space farther away from one's home provides more opportunities for deep restoration.
Section snippets
Data
The data for this study were derived from two separate datasets. The health data and data on stressful life events were collected within the framework of the second Dutch National Survey of General Practice (DNSGP-2), conducted in the Netherlands in 2000–2002 (Westert et al., 2005). The DNSGP-2 included a nationwide representative sample of 104 general practitioners practices with nearly 400,000 patients on their list. As part of the DNSGP-2 a random sample of 12 699 respondents participated in
Results
We first examined the correlations between the three health measures. The correlation between log-transformed number of health complaints and perceived general health was .41, p < 0.001, the correlation between log-transformed number of health complaints and log transformed perceived mental health was .42, p < 0.001, and the correlation between log transformed perceived mental health and perceived general health was .26, p < 0.001. Given that the three measures showed only modest correlations,
Conclusions and discussion
We investigated whether the presence of green space in people's living environment can buffer the adverse impacts of stressful life events on three self-reported health outcomes: number of health complaints, perceived mental health, and perceived general health. The results indicate convergent evidence across these health outcomes for buffering effects of green space within the wider living environment on the adverse impact of stressful life events. Green space in a 3-km radius around the home
Concluding remarks
In their influential book “The experience of nature: a psychological perspective” Rachel & Stephen Kaplan (1989) distinguish four progressive levels of restoration that require increasing time and intensity of the experience: clearing the head, recharging directed attention capacity, reducing internal noise, and finally “reflections on one's life, on one's priorities and possibilities, on one's actions and one's goals” (Kaplan & Kaplan, p. 197). Thus far, empirical research has focused mostly
References (55)
Exposure to restorative environments helps restore attentional capacity
Journal of Environmental Psychology
(2005)- et al.
Crossing boundaries and borders: regional science advances in migration modeling
Papers in Regional Science
(2004) - et al.
Noise and well-being in urban residential environments: the potential role of perceived availability to nearby green space
Landscape and Urban Planning
(2007) - et al.
Landscape planning and stress
Urban Forestry and Urban Greening
(2003) - et al.
Tracking restoration in natural and urban field settings
Journal of Environmental Psychology
(2003) The potential influences of environmental perception on human health
Journal of Environmental Psychology
(1991)- et al.
The view from the road; implications for stress recovery and immunization
Journal of Environmental Psychology
(1998) - et al.
The moderator-mediator variable distinction in social psychological research: conceptual, strategic, and statistical considerations
Journal of Personality and Social Psychology
(1986) - et al.
Transformations, means, and confidence intervals
British Medical Journal
(1996) - et al.
Quality of public open space tool (POST)
(2004)
The list of threatening experiences: a subset of 12 life event categories with considerable long-term contextual threat
Psychological Medicine
The list of threatening experiences: the reliability and validity of a brief life events questionnaire
Acta Psychiatrica Scandinavia
An environmental intervention to restore attention in women with newly diagnosed breast cancer
Cancer Nursing
A new measure for degree of urbanisation: the address density of the surrounding area
Maandstatistiek van de Bevolking
Natural environments-healthy environments? An exploratory analysis of the relationship between greenspace and health
Environment and Planning A
Bringing context back into epidemiology: variables and fallacies in multilevel analysis
American Journal of Public Health
Views of nature and self-discipline. Evidence from inner city children
Journal of Environmental Psychology
Some benefits of dichotomization in psychiatric and criminological research
Criminal Behavior and Mental Health
Een nationale studie van ziekten en verrichtingen in de huisartsenpraktijk. Basisrapport: meetinstrumenten en procedures
Environmental health disparities: a framework integrating psychosocial and environmental concepts
Environmental Health Perspectives
The detection of psychiatric illness by questionnaire
Seeking restorative experiences: elementary school teachers' choices for places that enable coping with stress
Environment and Behavior
Restorative effects of natural environment experiences
Environment and Behavior
Personality, life events, and subjective well-being: toward a dynamic equilibrium model
Journal of Personality and Social Psychology
Nature and health. The influence of nature on social, psychological and physical well-being
Environmental correlates of physical activity: a review of evidence about parks and recreation
Leisure Sciences
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This study was supported by a grant from the Netherlands Organisation for Scientific Research.