Smell the soil - become happy!
Mycobacterium vaccae a strain of bacterium in soil, has been found to trigger the release of serotonin, a neurotransmitter that elevates mood and decreases anxiety. It can enter the human body simply by hovering over the soil and breathing in, for example during gardening.
Discovery
The discovery of the effects of M. vaccae was something of an accident. An oncologist at Royal Marsden Hospital in London used the bacteria to create a serum for lung-cancer patients, in hopes of treating their symptoms. She found that patients showed an improved mood, being happier and feeling less pain than patients who were not treated with the serum.
Antidepressant
Doctor Lowry at Bristol University explored this further by injecting M. vaccae into mice and putting them in stressful situations. The mice that were injected had no problem coping with the stress test. A follow-up study done at the Sage Colleges in Troy, New York confirmed that feeding the bacteria to mice instead of injecting also led to better performance. The mice navigated a difficult maze faster and showed fewer signs of stress.
Dr. Lowry: "The bacteria had the exact same effect as antidepressant drugs."
Start sniffing dirt?
Simply inhaling M. vaccae seems to lead a happier state of mind, but you can get a dose by taking a walk in the forest, through gardening or ingesting the bacteria through eating home grown vegetables. It’s suggested in several articles that it could be a good way of treating a depression, but you won’t get high from sniffing dirt. The effects are proven to be there, but are more subdued than other euphoria-inducing substances.
Still, it’s a good excuse to start rooting in your garden or to take a long nature walk.
Read more:
Hortmag.com - Dirt can make you happy
Discovermagazine.com - Is dirt the new prozac?