For decades, scientists have been exploring how exposing humans to nature—by planting trees along urban streets, visiting forests or even just growing houseplants—may improve physical and psychological health. Now researchers are also testing whether we can reap at least some of the same benefits from experiencing nature in virtual reality. This strange twist speaks to some recent, powerful findings on the health impacts of nature exposure.
“We are seeing new research, really on a daily basis, coming out that is measuring, quantifying and showing the benefits of living and being in green places,” says Michelle Kondo, a research social scientist at the U.S. Forest Service. She says the recent bloom in research has been fed in part by medical records going electronic; this creates massive health data sets that scientists can compare to satellite views showing the relative greenness of each person’s neighborhood.
The growing body of analyses tends to show positive impacts of “green space,” which can mean natural areas or urban vegetation, on a wide range of health traits. “We know enough to be confident that [exposure to nature] is good for most people in most circumstances,” says Matthew Browning, an environmental psychologist and environmental epidemiologist at Clemson University.
For example, research from the past decade has shown that green space exposure can, among other things, reduce rates of early death, cardiovascular disease, obesity and type 2 diabetes. It is linked with better general perceived health as well, and a new study released last month reports that green space reduces “epigenetic aging,” an evaluation of biological age based on gene expression. “We are even seeing this at the molecular level,” says Usama Bilal, a social epidemiologist at Drexel University, who studies similar topics but wasn’t involved in the recent research.
In terms of psychological benefits, a 2019 review paper notes that nature exposure can lead to more positive emotional states, more social interactions and fewer negative emotions, as well as improved cognition, memory and attention, among other findings.
But all of these studies—and particularly the more conceptual work of trying to understand the connections between nature and health—are complicated by our abstract and varied definitions of “nature.”
How much nature do you need to see a significant benefit: a potted plant, a street tree, an urban park, an untouched wilderness? Are all ecosystems equally beneficial, or do forests, grasslands and beaches affect health differently? Do you need to smell and hear nature in addition to seeing it? The answers aren’t clear.
“When we’re in an environment, it’s a multisensorial experience,” says Gregory Bratman, an environmental psychologist at the University of Washington. “Before we can really know much about how the environment is impacting our well-being, we need to take all the active ingredients into account.”
One tool that might help scientists unpack what it is about nature that makes a real difference in health outcomes is virtual reality, says Hector Olvera Alvarez, an environmental health scientist at Oregon Health & Science University. He wanted to investigate whether simply seeing nature can relax people. Virtual reality let him expose experiment participants to the visual input of nature while controlling for factors such as temperature, light and air pollution. He is now preparing to publish his research.
“We believe that because we evolved around vegetation, we can assess safety faster in vegetated environments,” Olvera Alvarez says. “That’s why I was interested in VR because VR exposes you to the visual aspects of the natural environment. If the theory is right that we assess safety faster in nature, it should bring your stress levels down.”
So far, Olvera Alvarez says, research shows some health improvements associated with experiencing nature in virtual reality, although these benefits are smaller than those gained by exposure to real nature. The difference might be linked to virtual reality lacking what Bratman calls “ecological validity” because of the aspects of nature it doesn’t re-create.
“Even if you get everything right, the beauty of nature is you will never be able to capture it in the same way,” says Olivia McAnirlin, a social science researcher and environmental psychologist, who co-leads the Virtual Reality and Nature Lab at Clemson.
Some of her work has focused on people with chronic obstructive pulmonary disease, which can keep them stuck inside their house, sometimes for months on end. She identifies a natural place that’s meaningful to each person she works with, then re-creates these scenes in virtual reality, bringing at least a little bit of nature indoors.
In circumstances like these, virtual nature can offer an advantage—but that benefit shouldn’t come at the expense of exposure to real nature, says Browning, who co-leads the Virtual Reality and Nature Lab. “It’s a tool. It’s not a replacement,” he says of virtual reality. “We have to be careful with not pushing it in a way that would take money or attention away from investing in urban greening and parks.”
Such care is particularly important because poor and minoritized people—who already face worse health outcomes—often have less access to nature. And virtual reality is not feasible for everyone’s use because equipment can be expensive. This price tag puts VR out of reach for many of the people who could most benefit from exposure to virtual nature.
And the very same people with scant access to real nature may face the kinds of challenges that are more likely to be aided by real-world greenery than by virtual substitutes. Bilal says he’s particularly worried because virtual reality can’t replicate a key category of natural benefits he calls mitigation: city trees clean the air, reduce summer temperatures and absorb urban noise, for example. “There is a lot that comes with greener spaces. It’s not just seeing a beautiful tree in front of you,” Bilal says.
The same point holds true when scaled up from a neighborhood to the planet, says Gretchen Daily, an environmental scientist at Stanford University’s Natural Capital Project. She says she sees potential in the research on the benefits of virtual reality nature, particularly in situations where nature is currently lacking. But in the long term, humans absolutely must reconnect with nature in the real world—not through goggles and headsets.
“Part of me worries that there might be an idea that takes off that virtual reality can substitute for the real thing,” Daily says. “If that’s taken very far, that’ll be really harmful overall because the real thing is necessary in so many ways. We just cannot live on a dead planet.”