Picture the last time life got genuinely hard. Not inconvenient. Hard. A bereavement, a new baby, a relationship fracturing, a house move, a job that was taking everything you had. Lying awake at 3am with the same thoughts and lists circling. The hard conversation you know you need to have but keep putting off. Your gut knew before you did. That clench. That hollow drop. That squirm. Your gut instinct speaking as loudly as your mind because digestion changes when you are stressed.
Most people, when they stop and think about it, can trace their worst digestive periods directly to their most difficult life periods. The bloating that arrived the year everything fell apart. The IBS diagnosis that came six months into the most stressful job. The food reactions that multiplied during a period of grief or fear. We notice the pattern and then we dismiss it, because the story we have been given about digestion is mostly about food, and the story we have been given about stress is mostly about the mind. Nobody told us they were the same story.
They are the same story.
The science behind the gut-brain connection
The researcher Emeran Mayer, who has spent decades mapping the relationship between the brain and the gut, describes the gut not as a passive digestive organ but as a sensory system in continuous conversation with the brain, updating it constantly about internal state, threat and safety. That conversation runs primarily via the vagus nerve, and roughly 80 to 90 per cent of the signal travels upward, from gut to brain, not the other way around. Your gut is not receiving distress signals from your overwhelmed mind and reacting accordingly. It is an active participant in your nervous system, reporting in real time on whether the body feels safe.
When it does not feel safe, everything changes.
A large UK hospital study from St James’s in Leeds measured just how far this goes. Researchers looked at patients with active inflammatory bowel disease who also had clinically significant anxiety or depression. Compared to those with the same gut diagnosis but without those psychological symptoms, this group were many times more likely to flare, several times more likely to need treatment escalated and hospitalised at a dramatically higher rate. Same diagnosis. Same country. Same hospital. The difference was their emotional world.
Most people reading this do not have a Crohn’s or colitis diagnosis. But the mechanism is identical and the data simply gives us a way to count, in hospital admissions and treatment escalations, what your body has already been trying to show you, digestion changes when you are stressed.
What stress does to your microbiome
Then there is the microbiome, and this is the piece that most gut treatment is still not taking seriously enough. The trillions of bacteria living in your gut are producing around 90 per cent of your body’s serotonin. They are regulating immune activity. They are communicating directly with the vagus nerve and influencing the signals being sent to your brain. And they are acutely sensitive to stress and don’t forget, digestion changes when you are stressed.
Research from John Cryan at University College Cork, one of the leading scientists in this field globally, has shown that psychological stress measurably alters the composition of the microbiome within days, reducing microbial diversity, depleting the bacteria associated with calm and resilience and allowing more inflammatory species to take hold. The gut that feels chaotic under pressure has a bacterial landscape that has literally shifted in response to the threat state your nervous system is living in.
Chronic stress does not just make you feel anxious or exhausted. It changes the physical environment of your gut, the populations of organisms living there, the integrity of the gut lining, the reactivity of your immune system, which houses around 70 per cent of its activity in and around the gut wall, and the signals being sent back up to your brain. It is a loop. And once it is running, probiotics and elimination diets cannot close it on their own because they are not working at the level of the system driving it.
My own experience
I know this not just from the research. I know it from my own body.
There was a period in my life where almost everything I ate had a reaction. The list of foods I had to avoid had grown so long it had become its own source of anxiety, which of course made everything worse. It was exhausting in the way that only chronic low-level vigilance can be exhausting, that constant inner monitoring, that bracing before every meal, the need to always know where the nearest toilet was. What I did not recognise at the time was the grip of fear and stress I was holding in my body long before the food ever arrived.
When I began to rebuild my body with the nutrients it had been depleted of and started to release the fear responses I had been carrying, my digestion changed completely. I have been food intolerance free for over ten years. What I also came to understand is that the pattern was not entirely mine. My mother carried the same responses in her body and I had learned both the physiology and the fear from her, absorbing her relationship with food and stress before I had language for either.
How I work with this in clinic
The question most gut treatment never asks is what is your nervous system doing, and does it feel safe?
Treating the gut while the nervous system remains in a threat state is like mopping a floor after a flood while the tap is still running. You can keep adding fermented foods, cutting out gluten, rotating supplements. None of it will hold while the system generating the problem goes unaddressed. digestion changes when you are stressed
In my naturopathy practice in Kinsale and at The Natural Clinic in Cork, and working with clients online across Ireland, I address the nervous system, the gut and the immune system together rather than chasing symptoms one at a time.
Craniosacral therapy works directly with the central nervous system and with the enteric nervous system, the second brain living in your gut wall, using gentle touch to release the patterns of tension your body has been holding, often for years. When the nervous system begins to settle at that structural level, gut motility changes, immune reactivity quietens and the signals travelling up the vagus nerve begin to shift.
Somatic fascia release gives the body a way to discharge what it has been carrying. Fascia is not simply connective tissue wrapping your muscles and organs. It is threaded through with nerve endings, making it one of the richest sensory networks in the body and a direct participant in how your nervous system registers and holds stress. When life is hard for long enough, that stress organises itself into the fascia, creating patterns of holding that keep the nervous system primed and the gut reactive. When that held stress begins to move, the system is no longer running on old threat signals.
EFT shifts the patterns of thought and feeling that keep the stress response activated long after the original stressor has passed. Bach Flower remedies address the deeper emotional states those loops are running on, the fear that never quite leaves, the grief that has nowhere to go, the overwhelm that has become the baseline. Embodiment techniques bring you back into direct relationship with what your body is actually doing in response to the stories your mind is telling. The stomach that tightens when you think about a particular person. The throat that closes before a difficult conversation. These are your nervous system speaking in sensation, and learning to listen rather than override is one of the most powerful things you can do for your digestive health.
Nutritional support underpins all of it. Chronic nervous system activation depletes magnesium (check out my oil here Magnesium oil), B vitamins and the raw materials your gut lining needs to stay intact. We also look at fermented foods and what they can genuinely do for your microbiome once the nervous system is calm enough to let them work. Because that sequencing matters. You are not rebuilding a microbiome in a body that still feels under threat. You are rebuilding the house you live in, and that requires the foundations to be stable first.
If you have been managing your gut symptoms for years and nobody has yet asked what your nervous system is doing, that conversation is overdue. digestion changes when you are stressed
Sessions are available in Kinsale, at The Natural Clinic in Cork, and online. Book your first session here at loulanatural.com/make-a-booking or get in touch and tell me what is going on. I read every one.
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