As featured in Body+Soul on Sunday, 28th February, 2016.

We’ve probably all experienced the impact of nerves on our digestion; that sensation in the pit of your stomach that feels like a cross between a sinking brick and dancing butterflies that may also result in a quick dash to the loo. We have known of the intimate relationship between our nervous system and gut for a long time, with many naturopaths often referring to your gut as a ‘second brain’. We are now learning of the flip side to this relationship: how our gut health can impact our mood and nervous system. Here is what we know so far and what you should be aware of.

Bug-balance is the key

Our gut is like a big car park with lots of spaces for different bugs to live. New ways of testing has revealed we have close to 5 600 different species and strains living in us. Each of these bugs (or families of bugs) help keep us healthy by secreting substances that assist with metabolism. A skewed bug-balance created by frequent consumption of antibiotics, a gut infection/parasite or not giving our bugs enough TLC (i.e. having a poor diet and lifestyle) can lead to too many harmful secretions and not enough healthy ones.

The bugs in our gut are also involved in the production of neurotransmitters. These are chemicals that affect our brain and the way we think and feel. Our gut produces around 90% of our serotonin, one of our main ‘happy hormones’. An imbalance of bugs leads to imbalances in our neurotransmitters and as a result, may contribute to feelings of depression, anxiety or just feeling a bit ‘meh’. One of the big links that scientists are continuing to investigate is the gut-brain axis. This is a direct pathway from our gut to our brain thanks to the vagus nerve. This nerve pathway allows for 2-way communication between the gut and the brain and is allowing us to get a deeper understanding of whether diseases are imbalances in psychology or rather, digestion.

But before you go popping a probiotic, we also need to remember that our over-worked/stressed nervous system may have been the reason our gut imbalance first developed. It really is a case of ‘the chicken or egg’, but it’s generally better to do something as opposed to nothing. If you’re unsure where to start, get in touch with a naturopath who specializes in digestion and they will be able to help you figure out a plan.

Choosing the right probiotic

When choosing a probiotic, getting the right strain is important as each bacteria exerts very specific actions. When it comes to mental health these are some of the ones we know about (according to science) and that you should look out for: Lactobacillus brevis, Lactobacillus helveticus ROO52, Lactobacillus rhamnosis JB-1, Lactobacillus reuteri, Bifidobacteria dentium, Bifidobacterium infantis and Bifidobacterium longum. We also need to identify if you have a car park full of bad bugs! In this case, a probiotic should wait until you kill off those bugs that shouldn’t be there. Best to follow professional advice throughout this process.