Gardening gets us moving, fills our lungs with fresh air, is naturally meditative, and can be deeply nourishing, both literally and figuratively. But research also shows that in getting some dirt—with its bacteria and other microscopic denizens—under our fingernails, we may also boost our gut health.
The gut has earned the nickname “second brain” among some experts. Much of that is thanks to the 300 to 500 different types of bacteria, along with other friendly microorganisms, that make up our intestinal microbiome. From breaking down dietary fiber to making vitamins K and B7, the microbiome does a lot of heavy lifting in maintaining our well-being. A 2013 study at Oregon State University also found that gut microbes communicate back and forth with the vast number of immune cells that live in our gut, helping to decide when the immune system needs to spring into action—say, in response to invading bacteria—and when it isn’t needed.
Good for the Gardener
What, then, does gardening have to do with our gut? Soil naturally contains probiotic microorganisms that support gut health. For example, Mycobacterium vaccae, a bacterium found in soil, appears to aid the release of the chemical serotonin, which may alleviate anxiety and depression. “Gardeners inhale these bacteria while digging in the soil,” says microbiologist Dorothy Matthews from Russell Sage College in Troy, NY, as well as on “their vegetables, or when soil enters a cut in their skin.”
However, as modern science starts to discover the benefits of these probiotic microorganisms, our mainly indoor, sanitary lifestyles threaten their very existence and the delicate role they play in our bodies. Natalia Shulzhenko, PhD, who reported on the 2013 study, says our gut flora face “increasing disruption,” due to “modern lifestyle, diet, overuse of antibiotics, and other issues. With that disruption, the conversation is breaking down.”
All the more reason to go outside; get our hands dirty; breathe deeply; enjoy wholesome, natural foods; and care for the earth we all depend on.