Wednesday, May 1, 2013

Laughter, soil and serotonin

Studies confirm therapeutic value of gardening


As I write, I can hear the laughter of a neighbor boy, not quite old enough for grade school, as he helps his mother spread mulch in their garden. He's so proud of himself that he waves to whomever can see him on top of the great big mulch pile in his family's truck. His mom laughs with him as she calls out instructions.

Their laughter reminds me of an encouraging conversation I had the other day with new clients of my edible landscape design services. They told me how much better they feel when they are gardening, and that scientific studies had confirmed gardening's therapeutic value, as serotonin levels increase the more our hands are in the soil.
Reaping the benefits of gardening.


Our conversation prompted me to re-read articles that ran in the last few years about the benefits of bacteria in the soil. (See Discover, July 2007, and Horticulture magazine, January 2011). A 2007 neuroscientists' study showed an increase of serotonin when mice are exposed to Mycobacterium vaccae. These bacteria are found in the soil, particularly in cow dung. Serotonin of course lifts moods and helps with memory function, as well as plays a role in appetite regulation, sleep and other functions vital to a healthy life. The neuroscientists' study displays why cancer patients injected with M. vaccae report a better quality of life.

An April 2013 article in Mother Nature Network expounds on this concept by explaining how gardening strengthens the immune system and decreases the onslaught of allergies. Not only does gardening encourage a healthy balance of probiotics in the soil and in our stomach, but it also increases exposure to sunlight and the production of Vitamin D. Touching the earth is also said to reduce inflammation as negatively charged electrons flow through the body, neutralizing free radicals.

Studies also show that other common bacteria, staphylococcal, decrease inflammation when on the skin's surface, as reported in the United Kingdom's Telegraph. It's nice to see that large media outlets are covering the benefits of bacteria in the soil: The Washington Post (2010) and the Atlantic (2012) also ran articles about the M. vaccae studies.

In my home office, laughter continues to waft through the window from the outdoors. Gardening is good for our health on all sorts of levels—and I'm glad science is confirming why many of us are drawn to the soil.