The Stressed Gut

The Stressed Gut

When we have a stressful event in our lives that elicits a stress response, the downstream consequences on the gut are felt. We actually feel them in a very real way: that unease at the pit of your stomach, for example, or the nausea you may experience before talking in public – these feelings are the effects of stress signalling on the gut microbiome.


Stressed Gut & Malnourishment, Low Energy, Food Sensitivities and Inflammatory Processes

The first thing that happens, digestively speaking, when we are experiencing a stressful event, is hydrochloric acid production temporarily shuts down, affecting our ability to digest food properly. This is due to the essential role that stomach acid has in chemically breaking down the food we eat. So, chronic psychological stressors result in chronically poor digestive processes, and increasingly what is eaten is not absorbed or assimilated and the nutrients are not finding their way to the body’s cells. Cases of malnourishment, low energy, food sensitivities, inflammatory processes – are all borne of this mechanism.


What also happens is the immune system in the gut shuts down?


Bear in mind that 80% of the immune system lives in the gut. This phenomenon, in addition to a downregulation of stomach acid, allows stealth pathogens to penetrate through the bodies defence (which ordinarily would be a highly acidic stomach) and enter the gut and cause damage. Other stress hormones, like epinephrine and norepinephrine activate the opportunistic pathogens in the gut. These opportunistic pathogens ‘sense’ stress hormones and use that signal as an opportunity to take advantage, which generally results in leaky gut and inflammation. Over time, an imbalance between beneficial bacteria and opportunistic bacteria begins to develop.


The unhealthy inflammatory bacteria shift the microbiome towards a disease state. If we take the analogy of the gut as a garden – you want lots of flowers, but you don’t want lots of weeds- and the weeds are encouraged by stress hormones 24/7 in today’s society. We’re constantly watching the news and hearing about the world’s disasters, which tunes the nervous system into dangers which are not actually there for your body in reality. Usually, we are safe, and our fears are imagined. Taking control of how we think and feel demands practice that few people have the time or motivation to weave into their daily lives, but it can have a significant impact on gut health.


Taking control of how we think and feel


If you’re watching the news while you’re eating dinner, or sitting in traffic eating lunch, understand that the digestive tract is not ready to accept the gesture of food. Not enough digestive enzymes will be secreted, the ability to metabolize foods will be hampered, and this will ultimately lead to gut dysfunction. The internal intestinal lining is a one cell thick layer and has one of the fastest cell turnover rates in the body – turning over every three days. This high cell turnover rate requires tremendous amounts of energy, blood flow and nutrients for complete optimal regeneration.


A sympathetic nervous system ‘fight or flight’ response creates a lack of blood flow to the whole digestive tract, which prevents dysfunctions like leaky gut from healing. Leaky gut cannot heal without adequate blood flow, so all the gut healing nutrients that are often recommended to heal the gut barrier system (and you’ll hear me advocating for these daily in my practice), will only be truly effective in the absence of stressful events.


Support stress resilience and hasten the restoration of the gut dysfunction


There’s much we can do to support stress resilience and therefore hasten the restoration of the gut dysfunction, and if you’d like to learn more about how this plays out in practice, I’d be happy to help you.


Stay tuned for part II on this subject, where I’ll be focussing on the Vagus Nerve and its role in the gut-brain connection.



Nutritionist, Functional Medicine & Personalised Nutrition 


Brady Callander

BA (Hons), MSc Personalised Nutrition
Member of the Institute of Functional Medicine and The Royal Society of Medicine.
Advanced SIBO training with SIBO Australia