Understanding What Drives IBS &
Why Your Nervous System Matters

IBS is one of the most common digestive conditions, yet also one of the most misunderstood. It is not a single problem with a single cause. It is a pattern that affects digestion, gut sensitivity, the microbiome, hormones and, crucially, the nervous system.

Many people are told their IBS is “just stress” or something they must learn to live with. Others are given short-term dietary rules that offer partial relief but little clarity. In reality, IBS always has underlying drivers, and those drivers differ from person to person.

What IBS Really Is

IBS is diagnosed by symptoms, not by cause.

For most people, it reflects several things happening at once. Changes in gut motility, microbial balance, digestive strength and nervous system activation often overlap. Past infections, hormone shifts, low-grade inflammation, chronic stress patterns and conditions such as SIBO or dysbiosis commonly play a role.

This is why no two people experience IBS in the same way, and why personalised care matters.

The Gut–Brain Axis: The Missing Link

Your digestive system is directly regulated by your nervous system.

When your body feels safe, digestion tends to be steady. When it shifts into fight, flight, freeze or shutdown, digestion can become slow, painful or unpredictable.

Many people notice symptoms worsen during:

  • prolonged stress or overwhelm

  • emotional triggers

  • conflict or pressure

  • perfectionism and high self-demand

  • rushing or eating on the go

  • long-standing physical tension

IBS is not “in your head”. It is a physiological condition, with the nervous system acting as a major driver.

What Traditional IBS Advice Misses

Low-FODMAP diets, fibre supplements, probiotics, peppermint oil and antispasmodic medications can help manage symptoms, but they rarely address why IBS developed.

Commonly overlooked contributors include:

  • low stomach acid

  • inadequate digestive enzymes or bile flow

  • sluggish or irregular motility

  • microbial imbalance or SIBO

  • low-grade inflammation

  • hormonal shifts

  • diaphragm tension

  • freeze or fawn nervous system patterns

  • chronic stress physiology

  • emotional patterns held in the body

Without addressing these layers, symptoms often return when dietary control is relaxed.

What Actually Helps Long-Term

Lasting improvement comes from supporting the full system, not just controlling food.

This usually involves working across several areas:

Digestive function
Supporting acid, enzymes, bile flow and reducing inflammation.

Microbiome balance
Addressing overgrowths and rebuilding beneficial species.

Nervous system regulation
Reducing chronic stress signalling and restoring a sense of safety in the body.

Hormonal stability
Especially when symptoms fluctuate with the menstrual cycle or life stages.

Food confidence
Expanding the diet gradually, reducing fear around food, and identifying true sensitivities.

When your personal pattern becomes clear, IBS often feels far less confusing and far more manageable.

TLDR

What drives IBS
IBS arises from an interaction between digestion, the microbiome, hormones, gut motility and stress physiology. It always has underlying drivers, and those drivers are unique to you.

The role of the nervous system
Your gut responds directly to nervous system signals. Fight, flight, freeze or shutdown states can alter motility, sensitivity and digestion quickly. Supporting the nervous system is often key to lasting improvement.

In short
IBS is not a single issue. It is a gut–brain–microbiome pattern. When digestion, the microbiome and the nervous system are supported together, symptoms begin to make sense and improvement becomes sustainable.

Meaningful change comes from addressing the full picture. This is the Mind–Body–Biome approach.