Antidepressant microbes in dirt?

From Bonnie L. Grant, in Gardening Know How:

“Did you know that there’s a natural antidepressant in soil? It’s true. Mycobacterium vaccae is the substance under study and has, indeed, been found to mirror the effect on neurons that drugs like Prozac provide. The bacterium is found in soil and may stimulate serotonin production, which makes you relaxed and happier. Studies were conducted on cancer patients and they reported a better quality of life and less stress.

Serotonin has been linked to such problems as depression, anxiety, obsessive compulsive disorder and bipolar problems. The bacterium appears to be a natural antidepressant in soil and has no adverse health effects. These antidepressant microbes in soil may be as easy to use as just playing in the dirt.

Most avid gardeners will tell you that their landscape is their “happy place” and the actual physical act of gardening is a stress reducer and mood lifter. The fact that there is some science behind it adds additional credibility to these garden addicts’ claims. The presence of a soil bacteria antidepressant is not a surprise to many of us who have experienced the phenomenon ourselves. Backing it up with science is fascinating, but not shocking, to the happy gardener.

Mycrobacterium antidepressant microbes in soil are also being investigated for improving cognitive function, Crohn’s disease and even rheumatoid arthritis.

Antidepressant microbes in soil cause cytokine levels to rise, which results in the production of higher levels of serotonin. The bacterium was tested both by injection and ingestion on rats and the results were increased cognitive ability, lower stress and better concentration to tasks than a control group.

Gardeners inhale the bacteria, have topical contact with it and get it into their bloodstreams when there is a cut or other pathway for infection. The natural effects of the soil bacteria antidepressant can be felt for up to 3 weeks if the experiments with rats are any indication….”

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And furthermore, how wrong have we been about Serotonin and depression?

From Mad in America:

Revising the History of the Serotonin Theory of Depression?

Jonathan Leo, Ph.D. / Jeffrey Lacasse, Ph.D.

“The scientists on NPR discuss the fact that we now know that depression is much more complex than a simple serotonin imbalance. One guest describes the serotonin story as “late 20th century thinking.” Listening to the show, you get the impression that the serotonin theory was a viable contender just a few years ago; as of 1999, for instance, a psychiatrist telling her patients that they suffered from a serotonin imbalance would have simply reflected the current psychiatric thinking; and only recently have we learned that it’s much more complicated than this…

But what if this isn’t true? What if research has indicated for decades that the serotonin theory is false, yet psychiatrists told their patients the serotonin story anyway? What would this mean?

Here are a collection of selected material from books and articles covering the evolution of the serotonin theory. Pay attention to the year:

“By 1970…[George] Ashcroft had concluded that, whatever was wrong in depression, it was not lowered serotonin.” [D. Healy, Let Them Eat Prozac]

“…the biogenic amine theory [serotonin, norepinepehrine, dopamine] now more closely resembles a venerable flag than a tool we can work with…” [Bernard Carroll, 1982, cited in Before Prozac by E. Shorter].

“The simplistic idea of ‘the 5-HT [serotonin]’ neurone does not bear any relation to reality.” John Evenden, Astra pharmaceutical company research scientist, 1990 [See Before Prozac by E. Shorter].

1991: The antidepressant drug tianeptine lowers serotonin but is found to be an effective antidepressant [See Chamba et al., 1991]

Psychiatric historian David Healy argues that the serotonin story is a marketing ploy, 1997 [See D. Healy, The Antidepressant Era]

“Although it is often stated with great confidence that depressed people have a serotonin or norepinephrine deficiency, the evidence actually contradicts these claims.” [Neuroscientist Elliot Valenstein, 1998, in Blaming the Brain]

“In truth, the  “chemical imbalance” notion was always a kind of urban legend- never a theory seriously propounded by well-informed psychiatrists.” Ronald Pies, M.D., Editor of Psychiatric Times, in 2011

By the late 1990s and early 2000s, the scientific data on the serotonin theory was not only available to psychiatrists, but there were a series of popular-press books pointing out the problems with the theory, largely driven by experimental data from studies performed from the 1970s to 1990s. It seems reasonable to assume that practicing psychiatrists were just as informed about serotonin as members of the general public who read a book like Blaming the Brain or The Undiscovered Mind. Our current discussions take place 14 years after the publication of Blaming the Brain, and at least 20 years after scientific data showed clear problems with the serotonin theory….”

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