## Increase Tree Planting, Reduce Patient Admissions: A Fresh Perspective on Mental Health
A new analysis spanning multiple countries, published in **The BMJ**, reveals a significant link between greener surroundings and lower psychiatric hospital admissions. The research scrutinized over 11 million mental disorder hospital admissions across seven nations from 2000 to 2019. By evaluating data from Australia, Brazil, Canada, Chile, New Zealand, South Korea, and Thailand, the researchers found that greater exposure to green spaces was associated with a decrease in hospital admissions.
### Research Findings
Utilizing the Normalized Difference Vegetation Index (NDVI), the research team evaluated greenness at 6,842 sites. To ensure precise outcomes, various factors such as air pollution, temperature, and socioeconomic variables were taken into account. The aggregated data showed that an increase of 0.1 in NDVI correlated with a 7% drop in mental disorder admissions. This pattern was notably strong for substance use disorders, psychotic disorders, and dementia.
### Research Approach
The investigation used quasi Poisson time series models, factoring in environmental and socioeconomic influences. The protective effects were particularly significant in urban regions, where up to 7,712 hospital admissions could potentially be averted each year through enhanced greenness.
### Consequences for Urban Development
While the study does not confirm causation, it emphasizes the potential benefits of urban greening initiatives for mental health. Urban planners have the opportunity to utilize green areas, from street trees to parks, to possibly enhance public health and alleviate healthcare demands. The findings suggest that upcoming research should delve deeper into which types of green spaces offer the most advantages for mental well-being.
### Summary
Despite certain limitations, the study offers important insights into the connection between green settings and mental health. Promoting urban greening could act as a preventative approach, merging health objectives with environmental efforts. As mental health systems confront increasing challenges, incorporating nature into urban environments presents a promising pathway for enhancement.
[The BMJ: 10.1136/bmj-2025-084618](https://doi.org/10.1136/bmj-2025-084618)