The Winter 2007-2008 issue of Organic Gardening (a ghost of what it
used to be, unfortunately) has a blurb titled "Soil Makes You Happy":

Quote
Proof that dirty fingers lead to clean minds.
Findings: A common soil bacterium, Mycobacterium vaccae, is an
effective vaccine for leprosy. Researches began to evaluate its value
in treating asthma, tuberculosis, and cancer. When cancer patients
treated with M. vaccae reported feeling inexplicably happier,
neuroscientist Christopher Lowry, PhD., of the U.K.'s University of
Bristol injected mice with the bacterium, then examined their brains.
The mice's immune systems were stimulated, causing brain cells to
release serotonin, a mood-altering, pleasure-inducing hormone. Our
Advice: Dig in! Be happy!
--
Ann, gardening in Zone 6a
South of Boston, Massachusetts
e-mail address is not checked
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