A scoping study on the link between exposure to or interaction with the natural environment and mental health outcomes
Researchers found emerging evidence of the positive association between being in a natural environment or engaging with nature-based interventions on the one hand, and improvement in mental health on the other.
However, this research area is still in its infancy and the overall evidence base needs to be strengthened before any conclusive statements can be made.
There is some evidence that people are spending increasingly more time indoors than previous generations, and as a result we may be losing out on some of the health benefits that may come from spending time outdoors and in nature, such as physical health, wellbeing and subjective happiness. This issue could potentially be addressed by incorporating natural elements into architecture and building design, or “bringing the outdoors in.”
RAND Europe was commissioned by The VELUX Group to conduct a brief scoping study on the recent academic literature regarding the impact that exposure to nature has on mental health.
To address this request, the research team aimed to identify, analyse and synthesise available scientific literature that is related to the following research question: ‘Is there an association between exposure to or interaction with the natural environment and mental health outcomes?’
The study team conducted a scoping review of reviews using academic literature sources. Search terms and criteria were developed, and titles, abstracts and full-texts reviewed, before proceeding to full-text extraction and synthesis. An internal workshop was also held to discuss emerging findings and to identify different themes.
- The body of scientific literature relating to this area has been rapidly growing, from around 100 articles published per year in the 1990s, to almost 1,700 articles published in 2018. Despite this, the research area is still in its infancy and the overall evidence base needs to be strengthened.
- Owing to the diversity of types of interventions described, definitions of nature applied, the populations assessed and tools and methods used in the literature, it is not currently possible to amalgamate the findings into any one overarching conclusion.
- That said, the study highlights some emerging evidence of the positive association between being in a natural environment or engaging with nature-based interventions on the one hand, and improvement in mental health on the other. The authors found it useful to cluster the available evidence into four groups, largely defined by the parts of the population they address:
- The general population: Overall, most qualitative studies demonstrated an association between interaction with the natural environment and improved mental health, albeit not causally. The same was not true of quantitative studies, which tended to find no such association.
- Those with physical or mental illnesses: Evidence suggested a slight favouring of improved mental health and wellbeing for patients receiving nature-related therapy, however the results were not strong enough to make definitive judgements.
- Children and adolescents: In one review addressing this area, over half of the papers reviewed identified positive relationships between nature and mental health, including attention deficit disorder/hyperactivity disorder (ADD/ADHD), as well as overall mental health, stress, resilience and health-related quality of life (HRQOL).
- The impact of environment on mental health: One systematic review focused on the urban environment found that half of the papers reviewed reported natural elements, such as vegetation, botanical gardens, flowering meadow green rooves and green spaces, as having or predicting perceived restorative value for participants.