Time spent in the natural world benefits human health

Below Article appeared originally in The American Scientist.
July-August 2011Volume 99, Number 4 Page: 301

A Walk in the Woods » American Scientist.

A Walk in the Woods

Evidence builds that time spent in the natural world benefits human health

Anna Lena Phillips

For the month of April, I decided to visit the Haw River, which flows near where I live, every day. I wouldn’t hold myself strictly to this, but I would try, and I would observe—not impartially, of course, but closely—how I felt. Some days I took leisurely walks with friends, leaning over the railing of the pedestrian bridge to watch the river, high from recent rains, and to smell the distinctive, muddy smell of the water mingled with that of the banks overrun with invasive honeysuckle. On others, coming home late at night, I drove straight down to the bridge and walked out to stare down at the dark water, a move that felt a bit like the natural-world equivalent of visiting a drive-through restaurant.

I did this because I hadn’t been spending much time at the river, even though it’s only a short walk from home, and even though I like doing it. The results of my informal experiment? I did, in fact, feel better—calmer, more relaxed, clearer-headed. I suspect that many people have similar feelings about the effects of spending time in the wilder places near where they live. Perhaps that’s why Richard Louv’s 2005 book Last Child in the Woods, which explores the relation between the natural world and children’s development, became a bestseller in the United States.

2011-07SciObsPhillipsFA.jpgClick to Enlarge ImageBut to know empirically that these experiences are beneficial—and to know exactly how they might help us—requires more than personal experience. A growing and varied body of research attempts to quantify how and why spending time in the natural world might have beneficial effects on humans’ physical and psychological health. One of the first and most well-known studies, published in Science by Richard S. Ulrich in 1984, found that patients recovering from surgery in rooms with a window facing a natural setting had shorter hospital stays and took less pain medicine than did patients whose window faced a brick wall. Since then, researchers have asked whether the presence of trees influences people’s sense of safety in inner-city neighborhoods; explored how gardening might improve quality of life for people with disabilities; and used physiolgical measures to test for restorative effects of natural environments. If some of these studies seem too specific to be useful in answering the broader question, their results in sum suggest that time spent in nature improves human health. The more difficult questions are how, and in what ways, these effects arise. These questions are not the kind that can be answered by a single, groundbreaking paper; rather, like so many of the subtle and complex problems science explores, the evidence is being deposited, small study by small study, like layers of sediment on a river bed.

One such body of work is accumulating in Japan, where researchers are investigating the physiological effects of shinrin-yoku—“forest bathing,” or, to put it plainly, taking walks in the woods. Qing Li, a professor in the Department of Hygiene and Public Health at Nippon Medical School, Tokyo, has been involved with several such studies. He and his colleagues recently measured specific physiological markers before and after study subjects took walks in a forest and in an urban control environment. The study’s sample size is small—16 male subjects—and the timescale short—effects were measured after one day trip to the forest and one to the city—but the results suggest that the forest trip had positive effects on health. Subjects’ blood pressure measured in the forest was significantly lower when compared to measurements taken in the city. Levels of the stress hormone noradrenaline, measured in urine, were also significantly lower after the forest walk than after the urban walk. And blood levels of the adrenal hormone dehydroepiandrosterone sulfate (DHEA-S) and of adiponectin, a hormone secreted by fat tissue, were higher after the forest walk but not the urban walk. The authors note that DHEA-S may contribute to heart health, among other benefits, and that lower levels of adiponectin are associated with obesity and type 2 diabetes.

Li and his coauthors, whose study appeared in the European Journal of Applied Physiology in March, speculate that the forest trip’s effects on blood pressure may be related to phytoncides, volatile organic compounds (VOCs) that plants produce and release as protection from fungi and bacteria. In a separate study for which Li was also lead author, researchers unsurprisingly found higher concentrations of several phytoncides in a forest than in an urban area of Tokyo.

Another recent study, by Juyoung Lee, a researcher at the Center for Environment, Health and Field Sciences at Chiba University, Japan, and others, offers similar results. In this three-day field experiment, 12 young male subjects visited forest and urban environments. The study, published in February in Public Health, found that in the forest, subjects’ parasympathetic nervous-system activity was heightened and their sympathetic nervous-system activity suppressed. Pulse rates were lower, as were salivary levels of the adrenal hormone cortisol, which is associated with stress. Participants reported that their positive feelings increased, and negative feelings decreased, in the forest. Blood-pressure measurements, however, did not differ significantly between the forest and urban locations. The authors also measured phytoncide levels in the forest study area and found 10 different compounds, ranging in concentration from 0.3 micrograms per cubic meter to 1,336 micrograms per cubic meter.

In support of the idea that phytoncides may be responsible for some of the health effects seen in Li’s study, he and his coauthors cite a 2003 paper that found that inhalation of cedar-wood oil lowered blood pressure. A review article of forest-bathing studies, published in Environmental Health and Preventive Medicine in 2009 by Yuko Tsunetsugu and others, notes several laboratory studies that tested human responses to inhalation of plant VOCs. The results included such positive effects as lowered blood pressure and improved task performance. But to find a correlation between the mixture of phytoncides in forest air and physiological changes in humans would require experiments of more complex design. So although the idea that the very scent of the forest might improve health is appealing, determining whether it’s true and the extent of any effects will need more study.

This is just one of many avenues of inquiry that forest-bathing research opens. Can the physiological effects of studies like Li’s be replicated in larger studies, and in women and children? Do effects differ across gender and age? Do forests in varied bioregions, with different microclimates and compositions of tree species, vary in their effects on health? Do people who have grown up in one region experience different health effects in forests in their home bioregion than in other forests?

Policy questions abound as well. Carol Colfer, a cultural anthropologist and senior associate with the Center for International Forestry Research in Bogor, Indonesia, studies human use of forests in developing countries. “I suppose the logical result would be developing more or at least maintaining existing parks in cities, and expanding protected areas—but with much more serious attention to the human rights of people living in these areas,” she says of Li’s study. “Even better would be encouraging in situ conservation on people’s own lands.” Li is interested in exploring how his results could be used in medicine. “I am planning to develop forest bathing to be a preventive measure for some diseases such as depression, hypertension and cancers,” he says.

 

What’s clear is that trying to quantify a seemingly intuitive claim—humans benefit from spending time in the natural world—is turning up more complex answers, and more resulting questions, than a fir tree has needles. If policymakers take note of this work as it emerges, they might be better equipped to improve public health. For my part, I’ve extended my efforts to visit the river each day into the month of May. The weather’s better for swimming now, and the air smells as good as ever.

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Something Fishy in aBackyard Universe this morning..

I had just mentioned to someone last night, “Pay attention to birds because THEY will tell you what’s going on in the neighborhood or on the trail”   And it’s true, IF you do choose listen to Nature, she will share important things with you.  Like this morning as I was walking out onto the lanai to let the Chihuahuas out I heard this very distinctive call to my left…  

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The neighborhood Osprey was a lot closer to me than the last time I blogged about him – when he was 200′ distant in another neighbors yard…  So I quietly stood and fired off images until the Mockingbird chased him away.  That was a very narrow window I had to enjoy his presence in and I’m grateful for it!  I do hope someone else had the enjoyment of watching him with his meal, that everyone was not glued to the TV and missed an opportunity.

Seeing an Osprey close in like this is a rarity for me.  I’m not near a large body of water such as a beach or lake, so the Ospreys I see occasionally here have travelled to and from larger water sources, or perhaps fished the deep canal that runs along behind (to the East of)  Lehigh Acres Middle School, which isn’t far from me.  I do hope YOU had a chance to get outside this weekend and soak up some wonderful Vitamin N – the Nature Vitamin, and I hope you enjoy the photos.    

2,000 words+ that flew over me in an instant….

Image

Great blue heron color morph - White

Great blue heron color morph - White

Great blue heron color morph – White

If one picture is worth a 1,000 words.  This must be at minimum 2,000 words.  

I was sitting, reclining actually all bundled up and gloved for Winter on a swamp buggy at CREW Bird Rookery Swamp   I was looking all around us, as well as overhead at the Cypress trees, the alligator flags and into that icy blue sky scanning for photo targets; gators, butterflies.. small things  when out of somewhere he flew up and over us.  What a magical moment of surprise…..  Look how the sunlight streams through his feathers…..    Looking at the photos and re-visiting the moment I can feel him flying even now…    

Image of a Great blue Heron Color Morph – White.

a Little Bird Said: Go Star-Gazing!

I woke to the calls of a brilliant red sentinel Cardinal sitting up in the tops of the Mulberry Tree..  Today I’m planting out Nasturtium seedlings into pots and then  working on tonights Observing session for CREW Land and Water Trust.  Jim is busy adding a new Telrad to the LaVigne  10″ Dobsonian telescope for tonights use.

If you miss this evenings (Feb 9) Public Observing Session (Registration for tonight is closed)  at CREW we will offer another observing opportunity March 9th so if you happen to be in South West Florida visiting, or you live here, consider signing up via this link to attend our Family Star Gazing session.    

What will we see?  Jupiter, the Orion Nebula, various Star Clusters.. Galaxies M31 and M32 as well as pointing out numerous constellations and bright stars as well as telling some star-tails from CREWs beautiful Dark-Sky observing site I simply call Star Gazers Field.  If you go to the above Star Gazing link it will give you all the information about what you need to bring (don’t forget the blankets!) as well as where CREW Gate 5 is located.  Pre-Registration is required so check your calendar for March and include the Night Sky – Star Gazing, in your next family adventure into the Wilds of South West Florida! 

Sentinel Cardinal

Sentinel Cardinal

Weekly Photo Challenge: Green

This post is in response to the Word Press Weekly Photo Challenge  of the color GREEN.  I  also want to apologize for a month of non postings.  Scheduling issues, as well as health things got in the way of creativity.  But I should be back on track now to pick up the blogging so I hope you’ll stay with me and explore the richness of your backyard and community.  There really is allot to see out there and the first step to exploring it, is to go outside.  

To see the individual images larger, please click on them.

My choices for Green include a selection of small green insects, birds and amphibians you are likely to encounter either in your Florida backyard, or on a boardwalk at your local Nature Center or Preserve.  All of these green critters are quite small and can easily be missed if you’re hurried.  The Green Tree Frogs are found during the day resting up or hidden in leaves or along board walks.  The Green fly pictured on the big leaf is out in our yards daily, hanging around foliage, feeding off of rotted plant material.  The beautiful Iridescent Sweat Bees are normally found close to your grasses.. they move fairly slow so they are easy to follow around and study although I have seen them hovering high over trails at almost eye level when you step into their territory – last Friday I was able to hang around a good while watching their antics over the CREW Land and Water Trust trails.  

The Florida Green Anole can be a bit harder to find.  They have been replaced in many areas by invasive lizards (like the brown ones on your porches and lanais)  and loss of habitat.  This Anole is from Corkscrew Swamp Sanctuary, there you can find them along the boardwalks and on Alligator Flag leaves enjoying the sun, and looking for insects.  The beautiful, delicate Juvenile (he does not have his red throat yet) Ruby Throated Hummingbird is attracted to red flowers like Native Firebush, Red Shrimp Plants.  Vines, trees, and shrubs that attract hummers include honeysuckle, morning glory, trumpet creeper, albelia, butterfly bush, flowering quince, rose of sharon, weigela, flowering currant, rosemary, buckeye and horsechestnut, black locust, flowering crabs, hawthorns, mimosa, and tulip poplar.  I’ve also seen them feeding on the orchid like flowers of Bombax trees.  I hope you have enjoyed my selection of  “Green” and that it inspires you look around your local habitat for more of… the little things…         all photography by Linda S. Jacobson.

To see the individual images larger, please click on them.

Click here to visit my Artist Website

Weekly Photo Challenge: Free Spirit

 

 

This is my image submission for  the Word Press Photo Challenge of:  Free Spirit.

I love being out in nature, and I mean IN nature.. especially in the wetlands of our SW Florida swamps.  The peacefulness and variety of wildlife and plant life is amazing.   Numerous things abound to pique the senses at every sloggy turn.  Of course you’re soaking wet, maybe even up to your waist – careful, watch out for that fallen log you have to find a way to go over or under or that hole! – but that’s what your stick is for, probing ahead of your strides…  but…. the water is clear, cool and clean… I call it “refreshing” on a hot Spring day in South West Florida.  No, the water in the Swamp is not stagnant, it’s flowing along and you’re following it around the next turn and in my case, hoping I don’t fall down        (I tend to have problems with gravity.)  I feel best when I am out of doors, hiking a trail or wading in water with my camera and walking stick.

 

 

 

 

a favorite route to travel

 

             yeah, this is an   iPhone4GS   image from a truck

My favorite route to travel into Lehigh Acres from Fort Myers Florida, is along the Daniels Parkway corridor beginning from the Gateway turnoff, and heading East, into Lehigh.  Few other routes can take one through as many lush areas consisting of beautiful towering cypress domes, upland and marsh habitats.  Driving this nature corridor through out the year you may get to see:  wildflowers, turkeys, deer, hogs, alligators, otter as well as various wading birds, eagles and osprey.  Parts of this roadway have designated Panther Crossing signs at either end of it with separate day and night speeds so be aware.  During our fall and winter tourist season I often see other photographers up and down the corridor.

According to Greater Fort Myers Real-estate:  “Stretching from Gateway and Southwest Florida International Airport on the East to US-41 and the Shops at Bell Tower on the West, Daniels Parkway has emerged as Fort Myers’s  new “Main Street.”    I think of it more as the gateway to places like  CREW Land and Water Trust  and Corkscrew Swamp Sanctuary   Both part of the Corkscrew Watershed of which CREW alone comprises 60 thousand acres of protected watershed through Lee and Collier counties.

Should you visit Fort Myers Florida this Fall and Winter, consider spending some time along this scenic Daniels Parkway corridor.  Don’t forget to bring your camera and pack a lite lunch.  There’s allot to see and photograph for the patient imager.  And when you want more, go explore the offerings at CREW Land and Water Trust, and Corkscrew Swamp Sanctuary (links above.)    You won’t be disappointed!!!