How natural environments can promote health

As core members of the UK Centre of the Collaboration for Environmental Evidence, the European Centre for Environment and Human Health has pioneered the application of systematic review methodologies to environment and health issues. Our systematic review of the potential health impacts of environmental volunteering, the first ever mixed-methods Cochrane systematic review, clarified the key mechanisms for successful interventions and activities using natural environments for health and wellbeing. It found that environment-based interventions could result in health impacts through mechanisms including physical activity, social contact and personal achievement.

Our systematic review of the health and well-being benefits of biodiverse environments flagged the potential of thinking beyond ‘green space vs grey space’ for health and environment. It showed the mutual benefit of each and demonstrated significant inconsistencies and weaknesses in the evidence base, and the need for high quality, interdisciplinary research to better inform decision-making.

The scale of health economic values and wellbeing benefit of natural environments

In collaboration with Public Health England and Natural England, our research has shown that outdoor physical activity delivers an estimated £2.2bn worth of health benefits to adults in England each year. This study used Natural England’s unique Monitor of Engagement with the Natural Environment data to estimate physical activity associated with 1.13bn active visits per year to natural environments in England, and applied standard Metabolic Equivalent of Task ratios to estimate Quality-Adjusted Life-Year gains and their health-related economic values.

Further analysis identified a potential 120-minute/week threshold for outdoor activity to achieve health gains. This study estimated the relationship between actual time spent outdoors in nature (as opposed to residential proximity to green spaces) and self-reported health and subjective wellbeing. Our analysis identified this possible threshold, and the relationship was not solely explained through the increased physical activity associated with time outdoors.

Moving to greener neighbourhoods improves health

Our studies using the 18-year British Household Panel Survey were among the first to use robust longitudinal approaches to demonstrate that people moving to greener urban neighbourhoods have subsequent better mental health outcomes, and that positive effects last for at least three years following a move.

The novel use of long-term panel data permitted intra-individual analysis, improving causal inference relative to existing evidence at the time. In particular the approach reduced the likelihood that the observed greenspace-health association is due to selective migration of healthy, wealthy individuals toward greener areas.

Identification of opportunities and strategies for cross-sectoral policy and service delivery

Collaborative synthesis and policy-focussed research with Defra, Natural England and other Governmental partners identified opportunities to transform Defra’s role in promoting public health and the integration of health into the new Green Infrastructure Standards for England. Similarly, collaborative research with PHE and Local Authorities in the South West has informed how PHE works with local authorities to deliver health improvement through local government planning, environment and land use policy and delivery.

Supporting the linkage of environmental policy and social care practice, our systematic review on the value of natural environment engagement in care home settings demonstrated promising evidence of reduced agitation in care home residents with dementia who spend time in a garden.

This large interdisciplinary body of research has shown that the natural environment plays a critical role in delivering health and wellbeing benefits. We have also shown that the scale and likely causal pathways of these benefits have previously been underestimated and undefined.

Influencing national policy

At the national scale, the Centre’s research resulted in a joint report and departmental briefing that informed the Government’s position on natural environment and health. The report was produced by a collaboration between the Centre, Defra, PHE and related stakeholders, who synthesised existing evidence (including from Centre researchers) and conducted primary research.

This report, along with the key WHO report, were the key sources underpinning the health aspects of the UK Government 25 Year Plan for the Environment. Consequently, Defra has established policy commitments including the creation of national standards for Green Infrastructure, the transformation of agricultural subsidies to a focus on public goods (including health), environmental investments such as planting 11m trees by 2022, and large-scale initiatives.

Approximately £10 million has been committed to these health and nature programmes, reaching significant populations including over 500 schools.

Our evidence is influencing public health processes at the national scale, in part through our collaboration with PHE and the Health Protection Research Unit in Environmental Change and Health. Our research findings were used to establish the basis for the value of investing in urban green spaces for population mental health in PHE guidance to local authority planners Spatial Planning for Health; and in PHE guidance (co-authored by Dr Rebecca Lovell) on accessible greenspace, leading to the prominence of health in the new Green Infrastructure standards for England associated with the 25 Year Plan. Our work with Defra, PHE and the NHS, and evidence reviews of the impacts of nature-based health interventions have contributed to additional Government investment of £5m in social prescribing.