June 11, 2019 -- It's nearly 7 p.m. on a chilly spring day, and the gates of the lush, 127-acre Los Angeles County Arboretum & Botanic Garden have closed for the day.

It's time for a private event -- Forest Bathing: Full Moon Edition.

Certified guides Jackie Kuang and Debra Wilbur lead the 10 participants into the gardens, leaving behind the din of a wedding reception in a nearby building and several male peacocks in residence, shrieking and showing off their magnificent feathers.

As the group walks farther into the grounds the sounds change: birds, insects, wind in the leaves. Things that trigger other senses should come to play as well, such as the scents of the flowers and grass, the colors that pop from tree to tree. Over the course of the evening, the guides will issue four ''invitations'' for participants to commune with nature and, if they wish, share with others what it all means to them.

The practice of forest bathing, also called forest therapy, involves no bathing and isn't led by a therapist but a trained, certified guide or guides. In Japan, the practice is decades old and known as shinrin-yoku, which means "taking in the forest." Among the benefits, say practitioners and some researchers, are relaxation, less stress, connections with nature and, perhaps, insights to take home.

Critics often scoff that research about the practice is lacking, but there is growing scientific evidence that getting outside in a natural setting is good for mind-body health. And this back-to-nature movement isn't confined to forest therapy. Some medical doctors have trained to become forest therapy guides. Other health care providers are connecting their patients to nature in other ways. An Ohio cardiologist, frustrated that he couldn't convince his patients to exercise, founded Walk with a Doc in 2005, which now has 500 chapters. A Washington, D.C., pediatrician writes prescriptions for his patients to go to the park -- as do the more than 300 doctors and other health care providers who have signed on to his Park Rx America program.

The Forest Therapy Experience

Ben Page is used to people being skeptical of the idea of forest therapy, because anyone can head out to a forest or park and relax. Page, who founded Shinrin Yoku Los Angeles and is director of training for the Association of Nature and Forest Therapy, says ''a public park can be a rather distracting place. When you have a guide, it's a little bit like [the difference between] going to a yoga class with a teacher and watching a yoga video."

The association, which Amos Clifford launched in 2012, now has 625 guides either fully trained or in training, including 361 in the U.S. "In the last couple of years, we have had an increasing number of physicians who have trained with us and become guides," Clifford says. Other forest therapy associations, not affiliated with Clifford's, have also formed.

While Page has led forest therapy sessions in the Angeles National Forest and other locales, the popular arboretum sessions make the event more accessible to urban residents who want the opportunity closer to home, he says.

Forest Bathing, Urban Style

The group at the arboretum is diverse -- young adults, seniors, couples, singles. They first gather in a semicircle by the waterfall to exchange brief introductions.

The guides first encourage participants to relax their muscles from head to toe, and then notice the sounds, sights, and smells around them -- a rushing waterfall, a full moon hidden by an overcast sky, an aromatic herb garden, a rose garden.

The second invitation is to wander in the garden for 15 minutes.

Next is a stroll through the paved herb garden, with an invitation to pick something.

Finally, the group is invited to find a place that looks inviting and sit for a few minutes. Doing nothing for at least a few minutes can be healthy, the guides remind the group.

Walk With a Doc

David Sabgir, MD, a cardiologist in Columbus, OH, was frustrated that he could not convince most of his patients to do regular physical activity. "People had great intentions when they left the office," he says.

Then he hit upon a bold idea. He would ask patients to walk with him. That was in 2005, and ''we had 101 for the very first one." It's grown to 500 chapters worldwide, most of those in the U.S. The doctor leads the walk and gives a brief talk on a health topic. "We encourage people to walk 30 or 45 minutes if they can," Sabgir says. Unless bad weather forces the walk into a mall, the activity is outside, he says.

"It's a perfect way to break the ice with patients," he says. "There is something really special about getting outside the walls of the office, and being in nature." The feedback from patients, he says, is good. "They say they love it, and it's always in all caps."

Park Rx

Robert Zarr, MD, was also trying to get his patients -- children, teens and young adults -- moving and outside. The Washington, D.C., pediatrician formally launched Park Rx America in April 2017 and now counts about 325 health care providers -- mostly MDs, but also nurses, nurse practitioners, and physical therapists, among others -- who take part.

And yes, he literally writes a prescription for patients to go to a park. "The prescriptions that we do for parks are very flexible," he says. He asks his patients what they like to do. "The activity can be anything. It can be having a picnic outside, or a forest therapy session,'' says Zarr, who is a pediatrician at Unity Health Care and is training to become a certified forest therapy guide.

Research is accumulating on the healthful effects of contact with nature -- even very brief encounters. Among the findings:

  • As little as 20 minutes in a park boosted feelings of well-being, say researchers who surveyed 94 adults before and after visiting an urban park. The participants wore fitness trackers and completed a questionnaire before and after the visit.
  • Walking 15 minutes in a bamboo forest improved mood more in 60 adults than when they walked the same time period in a city area, other researchers report. Attention scores were better after the forest walk, too.
  • Forest bathing tends to lower cortisol levels, a marker of stress, better than taking part in other activities, a review of 30 studies found.
  • Forest therapy appears to lower depression levels in adults, according to a review of 28 studies.
  • Forest bathing also is found to boost the activity of natural killer cells, which help fight off infections and cancer.
  • The aromatic substances produced by plants and trees have been linked with lower inflammation and brain protection benefits.

What Forest Bathers Say

A coyote’s call from the guides brings the arboretum participants together again. This time, they gather in the Coach Barn, built in 1879 and still housing carriages from that era. Participants sit cross-legged on the wooden floor, and the guides pass tiny cups of rosemary tea, inviting all to sip and share their thoughts, if they wish.

Shay Sayani, 39, a Northridge, CA, holistic educator, says this is her third forest bathing experience. Now, she says, ''this is part of my self-care practice."

For Leon Adams, 68, a Glendale, CA, classical pianist, it was a first. "A friend recommended it," he says. "It took me a while to relax," he admits, but then he saw the rewards. "You leave the ‘monkey mind’ behind. You get into spaces in the mind that you can't get into when you are on the cellphone or in traffic."

On the walk back to the arboretum entrance, Kuang says she has introduced her 22-year-old son Chris to forest therapy. "He has autism and limited verbal expressions," she says. Forest walks ease his anxiety and improve his mood quickly. Her goal is to take him at least once a month. When he was asked by family to tell something that made him feel happy during the week, she says, he smiled and said ''forest walk."

Show Sources

International Journal of Environmental Health Research, Feb. 13, 2019.

Evidence Based Complementary Alternative Medicine, Feb. 11, 2018.

International Journal of Biometeorology, April 18, 2019.

International Journal of Immunopathology and Pharmacology, April-June 2007.

Toxicology Research, April 2017.

International Journal of Environmental Research and Public Health, March 2017.

Jackie Kuang, certified forest therapy guide.

Debra Wilbur, certified forest therapy guide.

Ben Page, founder, Shinrin Yoku Los Angeles; director of training, Association of Nature and Forest Therapy.

Amos Clifford, founder, Association of Nature and Forest Therapy.

David Sabgir, MD, cardiologist, Columbus, OH, and founder, Walk with a Doc.

Robert Zarr, MD, pediatrician, Unity Health Care, Washington, D.C.; founder, Park Rx America.

Shay Sayani, holistic educator, Northridge, CA.

Leon Adams, classical pianist, Glendale, CA.

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