"Forest bathing" (exposure to parks and forests) may increase immunity

American children today spend 90% less time playing outdoors than their parents did http://buff.ly/1aDk6ZY

"Shinrin-yoku", which can be defined as "taking in the forest atmosphere or forest bathing", has been receiving increasing attention in Japan in recent years for its capacity to provide relaxation and reduce stress.

The researchers have conducted physiological experiments, both in actual forests and in the laboratory, to elucidate the physiological effects on individuals of exposure to the total environment of forests or to only certain elements of this environment, such as:

- odor of wood
- sound of running stream water
- scenery of the forest

On one day, some people were instructed to walk through a forest or wooded area for a few hours, while others walked through a city area. On the second day, they traded places. The scientists found that being among plants produced “lower concentrations of cortisol, lower pulse rate, and lower blood pressure,” among other things.

Men who took two-hour walks in a forest over two days had a 50% increase in levels of natural killer cells.

References:

Trends in research related to "Shinrin-yoku" (taking in the forest atmosphere or forest bathing) in Japan. Tsunetsugu Y, Park BJ, Miyazaki Y. Environ Health Prev Med. 2010 Jan;15(1):27-37.

Exposure to Plants and Parks Can Boost Immunity - NYTimes.com, 2010.

Nature deficit disorder refers to a hypothesis by Richard Louv in his 2005 book Last Child in the Woods that human beings, especially children, are spending less time outdoors resulting in a wide range of behavioral problems.
http://en.wikipedia.org/wiki/Nature_deficit_disorder

Image source: A conifer forest in the Swiss Alps (National Park), Hansueli Krapf, Wikipedia, GNU Free Documentation License.

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