There's No Such Thing as Bad Weather: A Scandinavian Mom's Secrets for Raising Healthy, Resilient, and Confident Kids (from Friluftsliv to Hygge)

by Linda Åkeson McGurk

Some research suggests that low- or nonpathogenic strains of mycobacteria can help regulate the immune system and protect against allergic hypersensitivity. One of them, Mycobacterium vaccae, seems to have the ability to trigger our serotonin production, effectively making us happier and more relaxed. M. vaccae occurs naturally in soil and water, and is inhaled or ingested when we come in contact with dirt. Our exposure to mycobacteria has decreased considerably due to sanitation and water treatment in Western urban areas, but by regularly playing outside or helping out with a backyard garden, children can still get in contact with it. A recent study on mice also revealed that M. vaccae can improve cognitive functions, like learning. When researchers Dorothy Matthews and Susan Jenks at the Sage Colleges in Troy, New York, fed the bacterium to one group of mice, they were able to navigate through a difficult maze twice as quickly as the control group while being half as stressed. After the mice were taken off the M. vaccae diet, the effect of the bacterium gradually tapered off for about three weeks, at which point it disappeared. The researchers speculated that the M. vaccae not only helped the mice feel less anxious but also made them concentrate better. “Gardeners inhale these bacteria while digging in the soil, but they also encounter M. vaccae in their vegetables or when soil enters a cut in their skin,” Matthews told Therapeutic Landscapes Network after the results fr...