This section covers NIHR funded research into the impact of the built and natural environment (including green and blue space) on obesity. The built and natural environment refers to the physical environment in which people live, work and play (Public Health England). The built environment includes neighbourhood design, housing and transport. Green space includes parks, woodland, fields, and allotments (Public Health England). Blue spaces are outdoor water environments, natural or manmade, including rivers, lakes and the sea (Environment Agency).

What’s the context?

• The quality of the local environment contributes to activity levels and (excess) calorie consumption in daily life. Planning and designing the environment can help address obesity at the same time as contributing to environmental and sustainability goals (Public Health England).
• Local authorities can protect, maintain and improve local spaces – and create new open spaces – to help everyone move more without the need for direct, costly interventions (NICE).
• Equitable access to green and blue space are critical for maintaining and supporting health and wellbeing in local communities. Local authorities are asked to prioritise improved access to green space and to create greener communities, especially in areas of deprivation, as part of reducing health inequalities. They are advised to establish interventions, such as green social prescribing initiatives, that will encourage people to use green space, and promote individual and population health (Public Health England).
• A cross-government project is testing how to embed green social prescribing into communities in order to improve people’s mental health, reduce health inequalities, reduce demand on the health and social care system, and develop best practice in green social activities (NHS England).

What does NIHR research tell us?

Access to parks and the built environment affect rates of childhood obesity

Traffic-related air pollution and the absence of local parks are associated with higher levels of childhood obesity; the presence of parks is associated with decreased levels of childhood obesity. The number of intersections in an area (which indicates how easy it is to walk through an area) is also associated with obesity.(1) In studies around the world, proximity to green and blue spaces has been associated with increased physical activity, active travel, or reduced BMI in children.(2)

Exposure to green and blue spaces may increase physical activity and wellbeing

Living near green and blue spaces has been associated with health benefits, such as reduced risk of cardiovascular disease.(3) Other research has not found a clear association between health and exposure to green and blue spaces.(4) Improving footpaths, vegetation and community engagement, intended to increase the use of woodland in deprived areas, did increase physical activity levels. However, the increase in visits to natural spaces was low and no improvements were found in health or quality of life.(5) In other work, participation in environmental activities, such as nature conservation and litter picking, enhanced a sense of wellbeing. (6) More research is needed to show the long term impact on obesity.(4,6)

Major road expansion reduces physical activity and may increase health inequalities

Research has shown that major road expansions (i.e., new motorways) can reduce physical activity, promote car use and may increase health inequalities.(7) Traffic calming measures to create 20mph zones can reduce road accidents, but to date there is insufficient evidence of their impact on health outcomes, such as physical activity.(8)

Urban regeneration projects have not reduced obesity

Urban regeneration projects related to the London 2012 Olympics have so far shown only modest or temporary improvements in physical activity, and no beneficial effects on obesity.(9,10) This is despite improved access to sporting facilities and green space, and accommodation specifically designed for active living.

Useful resources

• The UK Government’s 25 year plan to manage and improve the environment.
• Natural England’s green infrastructure mapping database provides technical evidence on the green infrastructure in England.
• Public Health England has published a review on improving access to greenspace, including the role of local authorities.
• Public Health England has published a resource for planning and designing healthier places.
• NICE quality standard (QS183) encourages local authorities to involve community members in designing and managing public open spaces.

NIHR research in progress

• What effect have 20mph speed limits in Edinburgh and Belfast had on health?(11)
• What impact have Ultra Low Emission Zones (areas where polluting vehicles must pay a levy in order to use the roads) had in London?(12)

1. Malacarne D, Handakas E, Robinson O, Pineda E, Saez M, Chatzi L, et al. The built environment as determinant of childhood obesity: A systematic literature review. Obes Rev. 2022;23(S1):e13385.
2. Ortegon-Sanchez A, McEachan RRC, Albert A, Cartwright C, Christie N, Dhanani A, et al. Measuring the Built Environment in Studies of Child Health—A Meta-Narrative Review of Associations. Int J Environ Res Public Health. 2021 Jan;18(20):10741.
3. Dalton AM, Jones AP. Residential neighbourhood greenspace is associated with reduced risk of cardiovascular disease: A prospective cohort study. PLoS ONE. 2020 Jan 3;15(1):e0226524.
4. Geneshka M, Coventry P, Cruz J, Gilbody S. Relationship between Green and Blue Spaces with Mental and Physical Health: A Systematic Review of Longitudinal Observational Studies. Int J Environ Res Public Health. 2021 Jan;18(17):9010.
5. Ward Thompson C, Silveirinha de Oliveira E, Tilley S, Elizalde A, Botha W, Briggs A, et al. Health impacts of environmental and social interventions designed to increase deprived communities’ access to urban woodlands: a mixed-methods study. Public Health Res. 2019 Jan 9;7(2):1–172.
6. Husk K, Lovell R, Cooper C, Stahl‐Timmins W, Garside R. Participation in environmental enhancement and conservation activities for health and well‐being in adults: a review of quantitative and qualitative evidence. Cochrane Database Syst Rev. 2016(5).
7. Ogilvie D, Foley L, Nimegeer A, Olsen JR, Mitchell R, Thomson H, et al. Health impacts of the M74 urban motorway extension: a mixed-method natural experimental study. Public Health Res. 2017 Apr 28;5(3):1–164.
8. Cleland CL, McComb K, Kee F, Jepson R, Kelly MP, Milton K, et al. Effects of 20 mph interventions on a range of public health outcomes: A meta-narrative evidence synthesis. J Transp Health. 2020 Jun 1;17:100633.
9. Cummins S, Clark C, Lewis D, Smith N, Thompson C, Smuk M, et al. The effects of the London 2012 Olympics and related urban regeneration on physical and mental health: the ORiEL mixed-methods evaluation of a natural experiment. Public Health Res. 2018 Nov 9;6(12):1–248.
10. Berger N, Lewis D, Quartagno M, Njagi EN, Cummins S. Longitudinal associations between perceptions of the neighbourhood environment and physical activity in adolescents: evidence from the Olympic Regeneration in East London (ORiEL) study. BMC Public Health. 2019 Dec 30;19(1):1760.
11. Jepson R, et al. Is 20 plenty for health? Evaluation of the 20mph speed limit networks in Edinburgh and Belfast on a range of public health outcomes . [cited 2022 Jan 21].
12. Investigating the impact of London’s Ultra Low Emission Zone (ULEZ) on children’s physical activity and weight. ARC North Thames. [cited 2022 Jan 21].