Gut feelings

We all talk about ‘swallowing disappointment’, having something leave ‘a bad taste’ or having ‘butterflies in the stomach’. Now science is discovering why we do this, how it happens and how knowing about it can improve health and wellbeing.

What’s the focus all this new research? It’s our most unglamorous and workaday organ, the gut. Yes, the same organ that, according to Giulia Enders’ must-read book, Gut, ‘is responsible for little brown heaps, and unbidden sounds and smells of all sorts.’

By the gut, I mean the intestinal tube that starts from the gullet and ends at the anus. It’s the largest sensory organ in our body. It has its own nervous system, as vast as our brain, so complex that scientists call it the ‘gut brain’ or the ‘second brain’.

There’s massive communication between our gut and our brain and not only about what we eat and whether that makes us feel good or bad. It seems the gut can transmit messages to areas of the brain dealing with self-awareness, morality, fear, memory and motivation. That doesn’t mean our gut controls our moral thinking but allows for the possibility that the gut might influence it.

Recent experiments prove that feeling unwell and experiencing negative emotions can arise via the gut-brain nexus. For example, the vagus nerve is the fastest and most important route from the gut to the brain and experiments show that people can be made uncomfortable or anxious by stimulating the vagus nerve. So a gut that doesn’t feel good will affect our mental state and a healthy gut can improve our wellbeing.

Stress is among the most important stimuli discussed by the brain and the gut. When the brain senses a major problem, it diverts energy from the gut in order to solve that problem. The gut in turn supplies energy by saving on digestion, producing less mucous and reducing blood supply. When this goes on too long and the gut feels it’s had enough, it will signal the brain with signs ranging from fatigue to diarrhea. The situation’s not harmful in the short term but if it continues then over time the gut walls will weaken and the whole digestive system will begin to break down.

The gut, it seems, can also affect depression. Emeran Mayer* points out that neurotransmitters such as serotonin, dopamine and GABA – all of which affect our mood – are found in gut bacteria. In fact, 95% of the ‘happiness hormone’, serotonin, is produced in the gut. Confirmation of these links will interest irritable bowel syndrome sufferers, whose inclination to anxiety and depressive disorders is already well documented.

It’s too soon to say how these exciting new findings will be applied. Right now, for example, scientists are looking at how to block bad signals from gut to brain. They are also examining current medications such as antidepressants, designed for just the brain, to see how they affect or could be used to treat the gut as well.

What we do know is that this new research is extraordinarily important. It will make us reconsider the brain-body nexus and will revolutionise the way we manage pain management and mental issues. Till then, the take-home message is to look after both our bodies and our brains…and while we’re at it, to keep trusting our gut feelings.


  • Giulia Enders, Gut (Scribe Publications, 2014).
  • Emeran Mayer, Depression and the Mind-Gut Connection. 

What’s new

Springday Product Update

This month we’re launching one of our new health and wellbeing programs. MoveSmarter, a 5-week series developed by Exercise Physiologist Michael Usher delivers daily emails and videos to improve participants’ body posture, strength and movement. Request a demo today.

What else is going on?

Here are some interesting reads I’ve come across last month:

Our mood influences our reality: this article examines how the human brain creates certain states of mind and memory and how this influences our daily lives and mental health.

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This letter broke our hearts. Make sure to have a box of tissues handy when you read it. It’s a reminder of the importance of benevolence, appreciation and sharing the love we receive.

Check out these 35 young innovators who create tomorrow’s technology.

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Being happy at work can bring invaluable benefits to your business. However, employers who artificially try to create workplace happiness can do more harm than good.