Happy gardeners? It’s in the soil

You know how gardening improves your mood? Now there may be a scientific explanation for it. Soil makes you happy. And healthy. And smart.

Today’s sterile world may be adding to a whole list of diseases and health conditions.
As the old saying goes, “You need to eat a peck of dirt before you die”.

There are bacteria that are bad for us, of course, but also plenty of bacteria that are good for us, even necessary for health. Natural healthy soil is teeming with both. Mycobacterium vaccae, it turns out, is one of the good ones that’s common in soil and seems to have a positive effect on mood. M. vaccae, when it finds its way into humans (which it does orally, through open cuts or, more likely in adults, by being inhaled) stimulates neurons that produce the neurotransmitter serotonin. Increased availability of serotonin is how the antidepressant drugs known as SSRIs (including Prozac, Paxil, Zoloft) work.

M. vaccae is suspected of being quite the little wonder bug. It is under investigation as a treatment for cancer, Crohn’s disease, rheumatoid arthritis, asthma, psoriasis and eczema. Interestingly, these diseases have all risen in prevalence in the twentieth century, alongside the shift away from farm work to indoor work away from nature.

Most recently, a study with mice has indicated that the bacterium increases ability to learn.

Smarter, healthier, happier… we didn’t need more reasons to garden, but it’s kind of nice to have them.

M. vaccae, the happy-making bacteria.