How often do you need to be in nature for it to be beneficial?
We often hear we need to head outdoors more often, but is looking at a natural view from a window good enough? And what are the rewards other than physical activity?
David Furman, a researcher of longevity and inflammation at Stanford University in the United States, made headlines with his claims that he shaved off a decade of his biological age after a complete lifestyle overhaul that saw him live in the forest for three years.
His 'inflammatory age' – which he measured using a novel blood test he developed - dropped from 42 to 32.
Environmental psychologist Mathew White, from the University of Vienna, says it’s unrealistic to expect everyone to pack and move to the woods to improve their wellbeing, and even those who do would need a network of support (like proper infrastructure) to make their life not so stressful.
Dr Mathew White is a social psychologist researching the relationships between natural environments, physical health, and psychological health.
Supplied / European Centre for Environment and Human Health, University of Exeter
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“It's more interesting to think about how we can support those people living in cities [to] get out to nature.”
What’s wrong with our urban lifestyle?
Urban living has been beneficial for humans in many ways, but research is showing that, particularly in high-income countries, we have gone past “the point of balance”, White says.
In those places, life expectancy is going down and that appears to be linked with stress, obesity, lack of physical activity, he says.
“Interestingly, spending even just a couple of hours in nature a week seems to be associated with all of these things - better eating habits, more physical activity, lower stress, better sleep, more likely to be giving up smoking, some of the real big killers, and the things that are really affecting our telomeres and life expectancy.
“It's not a magic for everyone. We often look at averages but over whole populations, then we start to see a few hours a week can make a really big difference.”
People in poorer communities would benefit the most, he says.
“I'm a big proponent of improving the nature and green space in areas where lots of people live, and, again, in poorer communities.”
How does nature help us heal?
Other than the obvious physical benefits of moving our bodies, being in nature also helps people build resilience, White says.
“Time in nature isn't just about reducing stress now, it's about building your ability to cope with the challenges that you're going to get every day,” he says.
“When we expose people to nature before certain decision tasks, they tend to think clearer, they're more creative. So it can also give you a positive boost. In fact, many, many studies have shown that the positive emotions that you experience after nature are more powerful than the reduction in negative emotions from stress.”
A 12-year longitudinal study of more than 20,000 people found those who moved to a greener place reported improved mental health, and that “consistently stayed higher after the move”.
But to put it into perspective, “moving to a greener area is maybe something in the region of 7 [percent] to 10 percent of the effect on wellbeing of getting a job, if you've been unemployed, getting married after you've been single. So these effects are small for the individual.”
Although many studies rely on self-reporting, one of his studies monitored people’s brains while giving them mild electric shocks as they were shown natural settings.
“What you find neurologically is people's brains do not react to the electric shocks when they're in the virtual natural setting. So this isn't just them imagining it or telling a cultural story about all nature's good for us. Your brain is hardwired to not respond to pain in the same way when it's exposed to nature.”
Can’t I just look at it from my window or on my screen?
A study in Wellington found that residents with ocean views had lower levels of psychological distress. White says this “groundbreaking” study was replicated in Hong Kong among a population of older individuals, who found it hard to get out and about.
While for people with restricted mobility, the effects of viewing blue spaces from a window can be as good as being in nature, that might depend on the weather to some extent, he says.
“Watching a big storm come in across the sea might be fantastic from inside, but really not that comfortable when you're there. In general, we find that [the effect] indoor is less powerful in a sense, but it's still good if that's what you can get.”
How much time should we spend in nature to see benefits?
The exact time would depend on each person and their situation, White says, but research in England has shown 120 minutes is an important threshold.
The drop-off point of “diminishing marginal return” is after six hours, he says.
“There's two reasons for that. One, those people are often dog walkers, quite often a member of the family who's going out walking in all weathers and stuff. So spending more time out depends on what you're doing, if it feels like a chore.
“The other thing … is people who spend a lot of time in nature often have anxiety disorders or to some extent depression, but we find that people who spend most time in nature are actually seeking out the relaxation that it gives them.”
It also doesn’t matter if you split the 120 minutes across the week, he says.
“Fit it around the lifestyle that suits you.”
