Nature Contact and General Health: Testing Multiple Serial Mediation Pathways with Data from Adults in 18 Countries

Citation

Elliott, L. R., Pasanen, T., White, M. P., Wheeler, B. W., Grellier, J., Cirach, M., Bratman, G. N., van den Bosch, M., Roiko, A., Ojala, A., Nieuwenhuijsen, M., & Fleming, L. E. (2023). Nature contact and general health: Testing multiple serial mediation pathways with data from adults in 18 countries. Environment International, 178. doi.org/10.1016/j.envint.2023.108077

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Plenty of studies have shown that living near parks, lakes, or coastlines is good for your health. But exactly how nature delivers those benefits isn’t clear. Different studies have used different methods, focused on different populations, and tested different theories. This makes it hard to see the big picture.

A new study set out to change that. Researchers analyzed survey data from nearly 16,000 adults across 18 countries. THey looked at multiple ways neighborhood nature might improve general health. Could it be through cleaner air? More exercise? Stronger social connections? Greater well-being?

The answer, it turns out, is mostly about one thing: actually getting out and visiting these spaces.

The study tested a central idea — that the health benefits of nearby green spaces, inland blue spaces (like lakes and rivers), and coastal blue spaces don’t come just from living near them. Instead, they come from visiting them regularly, which in turn leads to more physical activity, more social contact, and greater well-being. The data supported this pathway for eight out of nine types of nature tested, and the results held up across a range of different statistical models.

When the researchers looked at whether factors like financial strain, sex, age, or whether someone lived in a city changed the results, they did find some differences. But those differences didn’t clearly show that nature was reduced health inequalities.

The takeaway is straightforward: across countries, the link between neighborhood nature and health works primarily through recreational contact. People who visit their local parks, lakes, or coastlines more often tend to be healthier — not just because the air is cleaner, but because those visits get them moving, connecting, and feeling better.

The researchers argue this is a strong case for investing in local green and blue spaces and making them easier and more inviting for people to use.

Abstract

Figure 1. A diagram of the proposed modelling approach. Direct effects from neighbourhood nature and nature visit frequency variables to general health are not shown for clarity. Solid lines represent direct, indirect, or potential confounding effects. Dotted lines represent residual covariances.

The role of neighbourhood nature in promoting good health is increasingly recognised in policy and practice, but consistent evidence for the underlying mechanisms is lacking. Heterogeneity in exposure methods, outcome measures, and population characteristics, little exploration of recreational use or the role of different types of green or blue space, and multiple separate mediation models in previous studies have limited our ability to synthesise findings and draw clear conclusions. We examined multiple pathways linking different types of neighbourhood nature with general health using a harmonised international sample of adults.

Using cross-sectional survey data from 18 countries (n = 15,917), we developed a multigroup path model to test theorised pathways, controlling for sociodemographic variables. We tested the possibility that neighbourhood nature (e.g. greenspace, inland bluespace, and coastal bluespace) would be associated with general health through lower air pollution exposure, greater physical activity attainment, more social contact, and higher subjective well-being. However, our central prediction was that associations between different types of neighbourhood nature and general health would largely be serially mediated by recent visit frequency to corresponding environment types, and, subsequently, physical activity, social contact, and subjective well-being associated with these frequencies. Several subsidiary analyses assessed the robustness of the results to alternative model specifications as well as effect modification by sociodemographics.

Consistent with this prediction, there was statistical support for eight of nine potential serial mediation pathways via visit frequency which held for a range of alternative model specifications. Effect modification by financial strain, sex, age, and urbanicity altered some associations but did not necessarily support the idea that nature reduced health inequalities.

The results demonstrate that across countries, theorised nature-health linkages operate primarily through recreational contact with natural environments. This provides arguments for greater efforts to support use of local green/blue spaces for health promotion and disease prevention.