Robyn Francis
Permaculture College Australia

While mental health experts warn about depression as a global epidemic, other researchers are discovering ways we trigger our natural production of happy chemicals that keep depression at bay, with surprising results. All you need to do is get your fingers dirty and harvest your own food.

In recent years I’ve come across two completely independent bits of research that identified key environmental triggers for two important chemicals that boost our immune system and keep us happy – serotonin and dopamine. What fascinated me as a permaculturist and gardener were that the environmental triggers happen in the garden when you handle the soil and harvest your crops.

Getting down and dirty is the best ‘upper’ – Serotonin

Getting your hands dirty in the garden can increase your serotonin levels – contact with soil and a specific soil bacteria, Mycobacterium vaccae, triggers the release of serotonin in our brain according to research. Serotonin is a happy chemical, a natural anti-depressant and strengthens the immune system. Lack of serotonin in the brain causes depression.

Ironically, in the face of our hyper-hygienic, germicidal, protective clothing, obsessive health-and-safety society, there’s been a lot of interesting research emerging in recent years regarding how good dirt is for us, and dirt-deficiency in childhood is implicated in contributing to quite a spectrum of illnesses including allergies, asthma and mental disorders.

At least now I have a new insight into why I compulsively garden without gloves and have always loved the feeling of getting my bare hands into the dirt and compost heap.

Harvest ‘High’ – Dopamine

Another interesting bit of research relates to the release of dopamine in the brain when we harvest products from the garden. The researchers hypothesise that this response evolved over nearly 200,000 years of hunter gathering, that when food was found (gathered or hunted) a flush of dopamine released in the reward centre of brain triggered a state of bliss or mild euphoria. The dopamine release can be triggered by sight (seeing a fruit or berry) and smell as well as by the action of actually plucking the fruit.

The contemporary transference of this brain function and dopamine high has now been recognised as the biological process at play in consumers addiction or compulsive shopping disorder. Of course the big retail corporations are using the findings to increase sales by provoking dopamine triggers in their environments and advertising.

I have often remarked on the great joy I feel when I forage in the garden, especially when I discover and harvest the ‘first of the season’, the first luscious strawberry to ripen or emergence of the first tender asparagus shoot. (and yes, the photo is my hand plucking a deliciously sweet strawberry in my garden) I have also often wondered why I had a degree of inherent immunity to the retail-therapy urges that afflict some of my friends and acquaintances. Maybe as a long-term gardener I’ve been getting a constant base-load dopamine high which has reduced the need to seek other ways to appease this primal instinct. Though, I must admit with the benefit of hindsight, I now have another perspective on my occasional ‘shopping sprees’ at local markets buying plants for the garden.

Of course dopamine responses are triggered by many other things and is linked with addictive and impulsive behaviour. I suppose the trick is to rewire our brains to crave the dopamine hit from the garden and other more sustainable pursuits and activities. As a comment on PlanetDrum stated, “all addiction pathways are the same no matter what the chemical. As long as you feel rewarded you reinforce the behavior to get the reward.”

So in other words it all comes down to the fact that we can’t change our craving nature but we CAN change the nature of what we crave.

Strengthening the Case for Organic

Glyphosate residues deplete your Serotonin and Dopamine levels

Of course, for all of the above to work effectively and maintain those happy levels of serotonin and dopamine, there’s another prerequisite according to another interesting bit of research I found. It appears it will all work much better with organic soil and crops that haven’t been contaminated with Roundup or Glyphosate-based herbicides. This proviso also extends to what you eat, so ideally you’ll avoid consuming non-organic foods that have been grown in farmland using glyphosates.

A recent study in 2008 discovered that glyphosate, the active ingredient of Roundup, depletes serotonin and dopamine levels in mammals. Contrary to Monsanto claims, glyphosate and other Roundup ingredients do perpetuate in the environment, in soil, water, plants and in the cells and organs of animals. One study found glyphosate residues in cotton fabric made from Roundup-ready GM cotton can absorb into the skin and into our nervous and circulatory systems.

No wonder there’s so much depression around, and stress, and all the addictions and compulsive disorders in the pursuit of feeling good. I think back on when I moved to Sydney in 1984 for a few years and was contacting community centres in the inner west to see if there was interest in permaculture or gardening classes. A very terse social worker snapped at me “listen dear, we don’t need gardening classes, we need stress therapy classes”, and promptly hung up on me with a resounding “Huh!” when I replied that gardening was the best stress therapy I knew.

So enjoy the garden, fresh organic food and make sure you have fun playing in the dirt on a regular basis.