That time in natural environments benefits health and well-being is well established, and the dose behind it is not. Physical activity has weekly guidelines; nature contact has none, because the relationship has barely been studied. So a English survey of 19,806 people, asked about their recreational nature contact in the previous seven days, was analyzed in hour-long blocks. Where does the line fall?
Nothing much below two hours a week, and little more above five. Compared with no nature contact, the likelihood of reporting good health or high well-being became significantly greater from 120 minutes upward. At 120 to 179 minutes the for good health was 1.59 and for high well-being 1.23. Associations peaked between 200 and 300 minutes per week with no further gain.
Spending time in natural environments can benefit health and well-being, which is not in much doubt. The exposure-response relationship is under-researched, which is why there are weekly guidelines for physical activity and nothing comparable for getting outdoors.
This analysis examined associations between recreational nature contact in the last seven days and self-reported health and well-being. Participants numbered 19,806, drawn from the Monitor of Engagement with the Natural Environment Survey across 2014 to 2016 and weighted to be nationally representative. Weekly contact was categorized using 60 minute blocks, and the analyses controlled for and other neighborhood and individual factors.
Compared with no nature contact in the previous week, the likelihood of reporting good health or high well-being became significantly greater at 120 minutes and above. In the 120 to 179 minute band the odds ratio for health was 1.59, with a 95 percent interval from 1.31 to 1.92. For well-being it was 1.23, with a 95 percent interval from 1.08 to 1.40. Positive associations peaked between 200 and 300 minutes per week, with no further gain beyond that.
Two details make the result more useful. The pattern held consistently across key groups, including older adults and people with long-term health issues. And it did not matter how the two hours were accumulated, with one long visit and several shorter ones equivalent. The authors are clear about what is missing. This is cross-sectional, so healthier people may simply go out more, and they call prospective longitudinal and intervention studies the critical next step.
wat. Two hours a week outdoors was where reported health and well-being started to lift, and five hours was where the lifting stopped.
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A threshold is what makes advice actionable. It also matters that it did not depend on how the time was accumulated, since one long walk and several short ones were equivalent.
How do we know?
White and colleagues analyzed 19,806 participants from the Monitor of Engagement with the Natural Environment Survey, weighted to be nationally representative. Weekly nature contact was categorized in 60 minute blocks, with residential greenspace and other factors controlled.
What is still unknown
This is cross-sectional survey data, so healthier people may simply get outside more. The authors say explicitly that prospective longitudinal and intervention studies are the critical next step before any guideline is written.
Learn something?
Where to next
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