Why Stress Is Silently Harming Your Gut (And How to Fix It)
Gut Health and Stress
Nearly 46% of Australians rated their stress level as 7 out of 10 or above in the past month, according to the 2024 Australian Community Survey by NCLS Research. And honestly, that tracks - I see it every week in clinic. So many women are carrying invisible loads: work deadlines, family responsibilities, financial strain, emotional fatigue… and it's showing up in their bodies, especially their gut.
In this blog, we’re unpacking the gut-brain connection, how stress impacts your digestion on a physiological level, and what you can actually do to support both your gut and your nervous system.
What Is Gut Health, Really?
“Gut health” might sound like a buzzword, but at its core, it’s about one thing: optimal digestive function.
Your gastrointestinal (GI) system is one long, highly intelligent tube that runs from your mouth to your rectum. It’s responsible for six essential processes:
Ingestion (eating)
Propulsion (moving food through the tract)
Mechanical digestion (chewing, churning)
Chemical digestion (enzymes breaking down food)
Absorption (pulling nutrients into the bloodstream)
Defecation (excreting waste)
Alongside these processes, organs like the liver, pancreas, and gallbladder support digestion. And then there's the microbiome - the trillions of microbes in your large intestine that help digest food, produce hormones, modulate immune responses, and influence mood.
When all of these systems are working in harmony, you feel energised, emotionally steady, and digestively comfortable. But when stress is involved, that harmony can quickly turn into chaos.
How Stress Physically Disrupts the Gut
Stress doesn’t just feel bad - it creates real, measurable changes in the body that can mess with your gut in multiple ways:
1. The HPA Axis: Your Body’s Stress Alarm System
When your brain perceives stress, the hypothalamic-pituitary-adrenal (HPA) axis kicks into gear. The hypothalamus releases signals to the pituitary gland, which then tells your adrenal glands to pump out cortisol - the body's main stress hormone.
Cortisol affects:
Stomach emptying (slows it down)
Colon contractions (speeds them up → diarrhoea)
Sensitivity in the gut (you feel every bubble, cramp, and burn)
2. The Microbiome-Gut-Brain Axis
The gut-brain axis is your internal communication system and stress can throw it completely off.
High cortisol levels can change the composition of your gut microbiome, leading to dysbiosis (an imbalance between good and bad microbes). This can cause symptoms like bloating, food sensitivities, low mood, and even brain fog.
3. Increased Intestinal Permeability (“Leaky Gut”)
Chronic stress can make your gut lining more permeable, allowing unwanted particles like undigested food and bacterial toxins to pass into your bloodstream. This triggers inflammation and may contribute to long-term gut and immune issues.
One marker of this process is lipopolysaccharide (LPS) - a compound released by harmful gut bacteria that’s linked to increased gut permeability and inflammation.
The Gut Conditions Linked to Chronic Stress
Stress is known to contribute to - or worsen - conditions like:
IBS (Irritable Bowel Syndrome)
IBD (Inflammatory Bowel Disease)
GERD (Reflux)
Peptic Ulcer Disease
Generalised GI discomfort
If you’ve been chasing down food triggers or trying elimination diets with no relief, it might be time to explore stress as the root cause.
Functional Medicine Labs That Can Help You Investigate
If you're struggling with ongoing gut issues and want real answers (not guesswork), these functional tests can provide insight:
Cortisol Testing (like the CAR Test)
Tracks your cortisol pattern across the day - especially important for identifying burnout or chronic high stress.
Comprehensive Stool Analysis (like the GI-MAP)
Looks at your microbiome, gut inflammation, and markers like calprotectin, zonulin (leaky gut), and pathogenic bacteria.
SIBO Breath Test
Detects bacterial overgrowth in the small intestine, which can be triggered by high stress and poor gut motility.
These tests go beyond “normal” GP checks and help create a truly personalised wellness plan.
Simple Ways to Support the Gut-Brain Connection Daily
You don’t need to meditate on a mountaintop or live on green smoothies to feel better. Here’s what you can realistically do to support your gut and nervous system:
Eat an Anti-Inflammatory Diet
Prioritise colourful fruits and vegetables
Choose whole grains, legumes, fish and olive oil
Include fermented foods (yogurt, kimchi, sauerkraut)
Reduce sugar, ultra-processed foods and alcohol
Practice Gentle Mind-Body Techniques
Deep breathing
Guided meditation or breathwork apps
Yoga or mindful walking
Even just 10 minutes a day can shift your nervous system into “rest and digest” mode.
Move Your Body (But Don’t Overdo It)
Moderate, regular exercise increases beneficial gut bacteria
Boosts production of SCFAs (short-chain fatty acids), which help reduce inflammation
High intensity workouts daily can increase stress load - balance is key
Explore Adaptogens and Probiotics
Ashwagandha may help regulate cortisol and reduce inflammation
Probiotics can restore microbial balance and support digestion, especially during times of high stress
Don’t Ignore the Stress-Gut Connection
Stress isn’t just a mindset issue - it’s a full-body disruptor. If your gut feels off, and nothing seems to help, it might be time to look beyond food and dig into your stress response.
Functional testing can help you get clarity, and small consistent lifestyle changes can dramatically shift how your gut - and your whole body - feels.
Need help exploring this further? Get in touch to learn more about gut-focused testing options or start integrating these strategies into your routine today.