A paean to Dirt

My wife and I have a much larger vegetable garden this year, as we're firmly committed to the ideology of Victory Gardens as a means of combating the environmental degradation. Several of my friends are also now becoming gardeners. One of them sent me the following email from her mother, which I'd like to share:

The reason gardening is euphoric may be that a soil bacterium helps lift depression. Am not kidding, it's in the July Discover magazine. The bug activates a set of seratonin-releasing neurons in the brain--the same nerves targeted by Prozac! Truly the world is mysterious and constantly amazing.

An inoffensive soil bacterium, called Mycobacterium vaccae, has been found to ease skin allergies as well as improve mood and lessen nausea in lung cancer patients. For experiments, the stuff is killed and broken up, then injected. It had the same effect on mice as antidepressants.

Here's the good part: Results so far suggest that simply inhaling M. vaccae--"you get a dose just by walking in the wild or rooting around in the garden--could help elicit a jolly state of mind. You can also ingest mycobacteria either through water sources [not specified] or through eating plants -- lettuce you pick from the garden, or carrots," according to one of the British authors of a paper in Neuroscience (online, March 28). Dunno if he means there's something special about those plants or they're just examples.

They think depression itself may be partly an inflammatory disorder. "By triggering the immune cells that curb the inflammation typical of allergies, M. vaccae may ease the inflammation and hence depression." (Hmm, depression is an allergy to life??) Future drugs might use the bacterium or be made from the same molecules.

Gotta love the Brit scientists: One of them sez, "It may be easier to say, 'The hell with it, let's use the bugs.' "

We're truly creatures of the earth, beholden to its germs. Wonder if the rise in depression and allergies can be traced to all the poison we've been pouring on the soil, killing the good bugs? And to spending so much less time outdoors? Air conditioning. Even I'm outdoors less because of mosquitoes and ticks, and the harsher sun. Do most kids still make mud pies? Here's to walking in the wild and rooting in the ground! Mud baths!


Two pals that keep my backyard's bug population down and my garden well fertilized.
---Thanks, Izzy. Enjoy, my friends and neighbors.