Count nearby green space when choosing where to live, but do not expect "going to the park more" to extend your life
Grade ASmall benefitLifespanFreeLittle timeNo willpower
The better the greenery within 500 meters of where you live, the lower the chance of dying over the same period. Counted as each 0.1 rise in the vegetation index, that chance is about 4% lower. What was measured is the greenery around the home, not how often you go to a park. In a greener area, the people who live there tend to have more money, and the air is better too. So do not take this as going to the park will extend your life. When you choose a home, count the green space around it.
- Cost
- No cost. When you look at a home, glance at the greenery around it.
- Benefit
- This pools 9 studies that followed groups of people for years (a meta-analysis of cohort studies), covering 7 countries and 8320000 people. It looks at greenery within 500 meters of the home, measured by the normalized difference vegetation index (NDVI, a number that converts ground vegetation into a score). For each 0.1 increase in the index, the pooled risk ratio for overall mortality was 0.96 (95% CI 0.94–0.97). The chance of dying over the same period was about 4% lower, and the true value falls roughly between 3% lower and 6% lower. Of the 9 studies, 7 found that better greenery went with lower mortality, and the difference did not look like chance. The other 2 found no link.
- Notes
- Disputed. Results across the studies differ widely (I²=95%; the larger this number, the less they agree with each other). And what it measured is greenery around the place of residence, not how often you go to a park. People who live in a greener place also tend to be richer, to have better air, and to exercise more, and these cannot be separated from the greenery as to which of them is doing the work. Do not read it as "going to a park extends your life." The usable part is to count green space when choosing a home, and the cost is 0. For this NDVI number, bare ground and concrete are near 0, and dense vegetation is near 1. So 0.1 is roughly the difference of moving from a bare block to a block with rows of street trees.
Sources · 1
- Rojas-Rueda D, Nieuwenhuijsen MJ, Gascon M, Perez-Leon D, Mudu P (2019). Green spaces and mortality: a systematic review and meta-analysis of cohort studies. The Lancet Planetary Health, 3(11), e469-e477. doi.org/10.1016/S2542-5196(19)30215-3