Gut-Brain Axis: Why Stress Shows Up in Your Gut
Understanding the powerful connection between stress, digestion, and your microbiome—and how to calm both
Written By: Megan Barefoot
Have you ever felt “butterflies” before a big event… or had your digestion completely off during a stressful week?
That’s not in your head—it’s in your gut.
Welcome to the gut-brain axis, one of the most fascinating and powerful systems in your body. This constant communication between your brain and digestive system is why stress doesn’t just affect your mood—it shows up physically in your gut. We have talked about this before with a connection to hormones but I want to put a different spin on it this time.
And if you’re dealing with bloating, irregular digestion, cravings, or even anxiety… this connection matters more than you think.
What Is the Gut-Brain Axis?
The gut-brain axis is a two-way communication system between your brain and your digestive tract, involving your nervous system, hormones, immune system, and microbiome.
Think of it like a constant conversation:
Your brain sends signals to your gut (stress, emotions, thoughts)
Your gut sends signals back (hormones, neurotransmitters, inflammation)
In fact, your gut is often called your “second brain” because of its extensive network of neurons and its ability to influence mood, behavior, and cognition.
Why Stress Shows Up in Your Gut
When you’re stressed, your body shifts into fight-or-flight mode.
This triggers a cascade of physiological changes that directly impact digestion:
1. Stress Hormones Disrupt Digestion
Cortisol and adrenaline slow down digestion, reduce stomach acid, and alter gut motility which leads to symptoms like:
Bloating
Constipation or diarrhea
Acid reflux
Stress is strongly linked to changes in gastrointestinal function and discomfort.
2. Your Microbiome Gets Out of Balance
Chronic stress can reduce beneficial bacteria and increase harmful microbes, creating dysbiosis.
This imbalance can:
Increase inflammation
Affect nutrient absorption
Impact cravings (especially sugar)
3. Inflammation Increases
Stress activates immune responses that increase inflammation in the gut, which can weaken the intestinal barrier and affect overall health. This is often referred to as “leaky gut” and this can make us increasingly sensitive to the foods we would normally eat.
4. Mood and Gut Health Are Deeply Connected
This is a BIG one! Your gut produces many neurotransmitters (including serotonin), meaning gut imbalance can influence:
Anxiety
Mood swings
Brain fog
The gut microbiome plays a key role in stress-related conditions like anxiety and depression. Our mental health is so important so eating for our microbes is not only important, it’s essential to how we handle stress.
Common Signs Your Stress Is Affecting Your Gut
I know you are likely reading this and either saying “Yes! This sounds like me.” or questioning yourself asking “Could this be me?” If you’re wondering whether this applies to you, here are some signs your gut-brain axis may be out of balance:
Digestive changes during stressful periods
Increased sugar or carb cravings
Bloating or discomfort after meals
Brain fog or low mood
Irregular bowel movements
Your body is always communicating—this is one of the clearest examples. It can simply be when you have a deadline to meet or a big meeting coming up. It could also be chronic as many of us are dealing with chronic stressors that just don’t seem to go away!
4 Ways to Support Your Gut-Brain Axis When You’re Stressed
I don’t want to leave you hanging so here’s the good news: you can actively support this system with simple, daily habits. It doesn’t have to be hard but some of these changes might feel a little uncomfortable until they are just your new normal.
1. Breathe Before You Eat
Taking just 3–5 deep breaths before meals activates your parasympathetic (rest-and-digest) nervous system, helping your body properly break down and absorb food.
👉 Simple shift: Slow down. Sit down. Breathe.
2. Build a Balanced Plate (PFF: Protein, Fat, Fiber)
This is my favourite and it should become your foundation for stabilizing both blood sugar and mood.
Protein → stabilizes energy and neurotransmitters
Healthy fats → support brain function
Fiber → feeds your gut bacteria
This directly supports microbiome health and gut-brain communication.
3. Add Fermented and Prebiotic Foods
Feed your microbiome daily with:
Fermented foods: sauerkraut, kimchi, kefir
Prebiotic foods: garlic, onions, asparagus, oats
Research shows diet can significantly influence the gut microbiome and stress response.
4. Regulate Your Nervous System Daily
This is the missing piece for most people.
Try:
Walking after meals
Deep breathing or humming
Gentle movement (yoga, stretching)
Prioritizing sleep
Even small daily practices can improve gut-brain signaling and reduce inflammation.
The Takeaway: Your Gut Feels What Your Mind Experiences
The gut-brain axis reminds us of something powerful:
Your body isn’t working against you—it’s communicating with you.
When stress shows up in your gut, it’s not random. It’s feedback.
And when you start supporting both your nervous system and your microbiome, everything shifts:
Better digestion
More stable energy
Improved mood
Reduced inflammation
If you’re ready to stop guessing and start understanding what your body is telling you, this is exactly the work we do at No Shoes Nutrition.
✨ Let’s get to the root of your symptoms—so you can feel clear, energized, and back in control of your health.
👉 Join my community, explore upcoming programs, or book a session at www.noshoesnutrition.com
References
Foster, J. A., & McVey Neufeld, K. A. (2013). Gut-brain axis: how the microbiome influences anxiety and depression. Trends in neurosciences, 36(5), 305–312. https://doi.org/10.1016/j.tins.2013.01.005
Morys, J. M., et al. (2024). Stress and the gut-brain axis: An inflammatory perspective. Frontiers in Molecular Neuroscience, 17, 1415567. https://doi.org/10.3389/fnmol.2024.1415567
Leigh, S.-J., Uhlig, F., Wilmes, L., Sanchez-Diaz, P., Gheorghe, C.E., Goodson, M.S., Kelley-Loughnane, N., Hyland, N.P., Cryan, J.F. and Clarke, G. (2023), The impact of acute and chronic stress on gastrointestinal physiology and function: a microbiota–gut–brain axis perspective. J Physiol, 601: 4491-4538. https://doi.org/10.1113/JP281951
