In a new study, researchers found that urban green space can prevent premature deaths.
The analysis, which included nine studies involving seven countries and a total of over eight million people, provides strong evidence on the impact of increasing green areas on mortality.
This is the largest and most comprehensive synthesis to date on green space and premature mortality.
The research was conducted by a team at the Barcelona Institute for Global Health (ISGlobal) and elsewhere.
Half of the world’s population lives in cities, where there is often a lack of green space.
Many studies suggest that green spaces in cities have a positive health effect, including less stress, improved mental health, and lower risk of heart disease, metabolic syndrome and premature death, among others.
However, many of these studies look at only one specific point in time and use different ways to measure exposure to greenness.
This is why the research team decided to summarize the available evidence and focus on studies that were longitudinal studies that follow the same cohort of individuals for several years.
They used a simple measure of exposure to green space. NDVI (Normalized Difference Vegetation Index) is based on satellite images, and the team and looked at premature all-cause mortality as a health outcome.
They identified nine studies worldwide that included over eight million individuals in total, from seven different countries (Canada, United States, Spain, Italy, Australia, Switzerland, and China).
The meta-analysis of these studies found that an increment in greenness around homes is significantly associated with reduced premature mortality.
More specifically, the study provides an estimate for the protective effect: a 4% reduction in premature mortality per each increment of 0.1 in vegetation score within 500 meters of the residence.
The results support interventions and policies to increase green spaces as a strategy to improve public health.
The lead author of the study is David Rojas, a researcher at ISGlobal and Colorado State University.
The study is published in The Lancet Planetary Health.
Copyright © 2019 Knowridge Science Report. All rights reserved.