The Mind-Blowing Benefits of a Nature Walk
It controls depression, improves athletic performance, helps battle colds, flu and cancer and has been shown to speed recovery time after sickness. A new medical marvel?
Nope. Just the great Canadian outdoors.
Scientists are increasingly finding links between our well-being and spending time in nature. But fewer and fewer of us are actually taking advantage of this. "We've turned our backs on the potential benefits of nature," says Alan Logan, the co-author, with Harvard Medical School's Dr. Eva Selhub, of Your Brain on Nature: The Science of Nature's Influence on Your Health, Happiness and Vitality. "Research going back decades has shown that even something as simple as a walk in the forest -- if you're really mindful of it -- has health benefits."
Fortunately, you don't have to live in the wild or wait for summer. A stroll down a path in a park, a favourite snap uploaded to your desktop or a nice view out the window will work wonders year-round.
Seeing the forest for the trees
According to research by the Department of Hygiene and Health at Nippon Medical School in Tokyo, the relatively recent practice of shinrin-yoku ("forest bathing"), or a walk through trees, does more than pass the time. Scans have shown that after just 20 minutes, blood flow in the brain changes to a state of relaxation.
And it can improve immune function, too. Blood tests by Nippon Medical School researcher Qing Li revealed that a day trip to a forest increased the number of natural killer cells the body produces to battle infection and made them more active for up to a week later.
Perhaps less surprising is how nature can improve mood. In work by Dr. Marc Berman at Baycrest's Rotman Research Institute in Toronto, depressed adults showed marked improvements in not only mood but also memory function. So how does it work? Researchers are still debating that, but Berman says it's partly to do with how our attention operates. Whether we're focused on natural surroundings or not, our involuntary attention -- the one that gently registers birdsong, the wind in leaves and the smell of fresh earth -- revitalizes a fatigued mind. Plus, you don't even have to like it to receive the benefits. In Berman's research, patients took walks in June and in January; they didn't enjoy the midwinter stroll as much -- no surprises there -- but they still experienced improved memory and mood.
Part of the answer might also come from the trees themselves. Experimental studies have shown that phytoncides, the olfactory-provoking chemicals that trees naturally secrete, can lower our production of stress hormones, reduce anxiety and increase our pain threshold. Inhaling aromatic plant chemicals, in fact, increases the antioxidant defence system in the human body, says Logan. And they can be cancer-protective: one Nippon Medical School study found a correlation between the amount of forest around you and cancer-mortality rates. In other words, this could suggest that the more forest, the lower the rates of lung, breast, uterine, prostate, kidney and colon cancers.