IBS Is BS: A Name for the Symptoms, But What About the Cause?

“You have IBS.”

Three words that can bring relief to someone who has spent months, sometimes years, trying to understand why their digestive system seems to have a mind of its own.

But for others, those same three words can feel like the beginning of an entirely new frustration.

Perhaps you have been experiencing persistent bloating, abdominal pain, unpredictable bowel movements, constipation, diarrhoea, or a combination of symptoms that never seem to follow a consistent pattern.

You have tried eliminating foods, taking probiotics, changing your diet, and perhaps undergone blood tests, stool tests or other investigations.

And eventually, you are told that you have Irritable Bowel Syndrome (IBS).

But what does that actually tell you?

Does it explain why your symptoms began? Why certain foods suddenly seem intolerable? Why your digestion changes during stressful periods? Or why two people with the same diagnosis can experience entirely different symptoms?

Not necessarily.

And this is where I think IBS is one of the most misunderstood diagnoses in digestive health.

Before we go any further, let me clarify something important.

I don't believe IBS is a made-up condition. I don't believe its symptoms are imaginary, and I certainly don't believe that everyone diagnosed with IBS has an undetected disease waiting to be discovered.

IBS is real. The pain is real. The disruption to everyday life is real.

What I question is the idea that naming a condition always means we have fully explained it.

As a naturopath, this distinction is central to the way I approach digestive health.

Because sometimes, the most important question isn't simply what condition does this person have?

It's what is contributing to this person's experience of it?

IBS Is Real. The Misunderstanding Is the BS.

Irritable Bowel Syndrome is a recognised disorder of gut–brain interaction, commonly referred to as a DGBI.

This means that symptoms can arise from changes in how the digestive system and nervous system communicate, even when routine investigations do not identify structural damage or an obvious disease process.

The gut is not simply a tube that processes food.

It contains its own extensive network of nerves, known as the enteric nervous system, and communicates continuously with the brain through neural, hormonal and immune pathways.

These systems help regulate digestive movement, secretion, sensation and responses to what we eat and experience.

In IBS, several aspects of this communication may function differently.

Some people experience increased sensitivity to normal intestinal stretching. Others have changes in bowel motility, meaning food and waste may move through the digestive tract differently.

Altered microbial activity, immune signalling and previous gastrointestinal infections may also contribute in some individuals.

The important point is that IBS does not have one universal mechanism.

And this helps explain why two people with the same diagnosis may have very different experiences.

One person may experience predominantly constipation. Another may have frequent diarrhoea. Someone else may alternate between the two, while another struggles primarily with abdominal pain and bloating.

These are not necessarily different diseases, but they may involve different combinations of physiological processes.

So when we say IBS is a disorder of gut–brain interaction, we are not saying it is simply psychological.

We are acknowledging that digestive function is regulated by an interconnected biological system.

And that system deserves to be understood.

The Problem With Calling IBS Idiopathic

The word idiopathic is used in medicine when the cause of a condition is unknown or cannot be clearly established.

IBS is sometimes described this way because there is no single identifiable cause that explains every case.

But I think the term can be misunderstood.

An unknown cause does not mean there are no known biological mechanisms.

And it certainly does not mean there is nothing worth investigating.

Importantly, IBS is not formally defined simply as an idiopathic condition. Modern gastroenterology recognises it as a disorder of gut–brain interaction with established diagnostic criteria and several proposed and demonstrated physiological mechanisms.

This is an important distinction.

Historically, IBS was often approached as a diagnosis of exclusion.

In other words, once other diseases had been ruled out, IBS became the explanation.

Today, clinical guidelines recommend a more positive diagnostic approach.

Rather than requiring every conceivable investigation to be negative, clinicians can identify IBS through a characteristic symptom pattern, clinical history and appropriate targeted testing.

Under the established Rome IV criteria, IBS involves recurrent abdominal pain associated with bowel movements or changes in stool frequency or appearance, with specific requirements for symptom frequency and duration.

Bloating and altered bowel habits are common, but bloating alone does not establish an IBS diagnosis.

This approach can reduce unnecessary testing and help people access treatment sooner.

However, there is an important difference between making an appropriate diagnosis and assuming that the diagnosis answers every question about a person's symptoms.

IBS can be a valid diagnosis without being a complete explanation of an individual's digestive experience.

And that is where I believe a more individualised approach becomes valuable.

So What Might Be Contributing to IBS?

When I look at digestive symptoms, I am interested in understanding the circumstances in which they developed.

Not because I expect to uncover one hidden cause in every patient, but because several different factors may influence the same symptom pattern.

1. The Gut–Brain Axis and Nervous System

Have you ever noticed that your digestion changes when you are anxious, overwhelmed or under pressure?

Perhaps your stomach tightens before an important event. You suddenly need to use the bathroom when you are nervous, or your appetite disappears during a particularly stressful period.

These experiences reflect genuine physiological communication between the brain and digestive system.

Stress-related signalling can influence intestinal movement, secretion and pain sensitivity.

For someone already experiencing IBS, these changes may contribute to symptom fluctuations.

But this relationship works in both directions.

Persistent digestive symptoms can themselves create anxiety, disrupt sleep and increase vigilance around eating or leaving the house.

The nervous system can influence the gut, and the gut can influence how we feel.

This does not mean stress caused someone's IBS, or that managing stress alone will resolve it.

It means the nervous system may be one relevant part of a much larger picture.

2. The Gut Microbiome

Our digestive tract is home to a complex ecosystem of microorganisms that participate in fermentation, metabolite production and interactions with the immune system.

Research has identified differences in microbial composition and function in some people with IBS.

However, the findings are not consistent enough to establish one characteristic IBS microbiome.

There is no single bacterial species, diversity score or commercial microbiome result that can reliably diagnose IBS or identify its cause.

And although microbiome testing is an evolving area of research, many commercially available tests have limited proven clinical utility for directing individual IBS treatment.

This is where I think we need to be careful about the language we use.

Terms such as dysbiosis are frequently presented as though they are diagnoses in themselves.

But identifying a microbial difference does not automatically establish that it caused someone's symptoms.

We need to distinguish between an association, a plausible mechanism and a demonstrated cause.

The microbiome may be part of the story. It should not automatically become the entire story.

3. Previous Gastrointestinal Infections

One particularly interesting area of IBS research is post-infectious IBS.

Some people develop persistent abdominal pain and altered bowel habits after an episode of infectious gastroenteritis.

Even after the original infection has resolved, changes in gut sensitivity, immune activity, motility or microbial function may persist.

This is one of the clearest examples of why taking a detailed clinical history matters.

If someone tells me their digestive symptoms began after food poisoning, overseas travel or a significant gastrointestinal infection, that information may help us understand the development of their symptoms.

It does not necessarily mean an infection is still present or that antimicrobial treatment is required.

But it provides context that may otherwise be missed.

4. Food Sensitivities and Fermentation

Food is often the first thing people blame when digestive symptoms appear.

And understandably so.

If eating seems to trigger bloating, pain or diarrhoea, it is natural to start looking for foods to eliminate.

But a reaction to a food does not always mean an allergy, intolerance or inflammatory response.

Some carbohydrates are poorly absorbed in the small intestine and fermented by intestinal microorganisms.

These carbohydrates are known as FODMAPs.

In susceptible individuals, they can increase intestinal water content and gas production, contributing to symptoms such as bloating, pain and altered bowel habits.

A low-FODMAP diet is one of the more extensively researched dietary interventions for IBS.

However, it is intended as a structured, temporary restriction phase followed by reintroduction and personalisation, not a lifelong list of foods to avoid.

This matters because I regularly see how easily people can become fearful of food when their digestion feels unpredictable.

The goal should not be to eliminate as many foods as possible.

The goal is to identify what genuinely influences symptoms while preserving nutritional adequacy, dietary variety and a healthy relationship with food.

5. Motility and Visceral Hypersensitivity

Two concepts that deserve more attention in IBS are motility and visceral hypersensitivity.

Motility describes the movement of contents through the digestive tract.

Visceral hypersensitivity refers to increased sensitivity to sensations arising from internal organs.

In some people with IBS, normal amounts of intestinal gas or stretching may be experienced as unusually uncomfortable or painful.

This is not imagined pain.

It reflects differences in how sensory information is transmitted and processed.

Changes in motility may also contribute to constipation, diarrhoea or unpredictable bowel patterns.

Understanding these mechanisms helps explain why someone may experience significant symptoms despite having normal-looking results on routine investigations.

A normal scan does not mean the digestive system is functioning normally in every respect.

And it certainly does not invalidate someone's experience.

When IBS Isn't the Whole Story

This is where a careful clinical assessment becomes particularly important.

Not every person experiencing bloating, abdominal discomfort or altered bowel habits has IBS.

Several other conditions can produce overlapping symptoms.

Depending on the person's presentation, relevant considerations may include:

• Coeliac disease: An immune-mediated condition triggered by gluten in genetically susceptible individuals. Appropriate testing is particularly important in people presenting with IBS-like diarrhoea.

• Inflammatory bowel disease: Conditions such as Crohn's disease and ulcerative colitis can cause abdominal pain and altered bowel habits. Blood and stool inflammatory markers may help determine whether further investigation is needed.

• Bile acid diarrhoea: Excess bile acids reaching the colon can contribute to chronic watery diarrhoea and may be mistaken for diarrhoea-predominant IBS.

• Microscopic colitis: A condition that can cause persistent watery diarrhoea despite a colon appearing normal during examination. Diagnosis requires appropriate biopsies.

• Carbohydrate malabsorption: Lactose and other poorly absorbed carbohydrates may contribute to symptoms in some people.

• Pelvic or gynaecological conditions: Endometriosis, for example, may cause bowel-related pain or symptoms that overlap with IBS.

Small intestinal bacterial overgrowth (SIBO) is another frequently discussed possibility, although its relationship with IBS is complex. Breath testing has limitations, and SIBO should not be assumed to be the cause of every case of bloating.

These conditions do not all need to be investigated in every person.

Testing should be guided by symptoms, medical history, examination, risk factors and clinical judgement.

Equally, certain symptoms should prompt further medical assessment rather than simply being attributed to IBS.

These include unexplained weight loss, gastrointestinal bleeding, iron-deficiency anaemia, persistent fever, new or progressively worsening symptoms, or a relevant family history of colorectal cancer or inflammatory bowel disease.

New bowel symptoms at an older age, particularly with other concerning features, also warrant appropriate assessment.

The intention is not to frighten people into pursuing endless investigations.

It is to ensure that a familiar diagnostic label does not prevent us from recognising when something else may require attention.

A whole-person approach means knowing when to look beyond IBS, but also recognising when further testing is unlikely to provide meaningful benefit.

The Root Cause Perspective: Looking Beyond the Label

The phrase root cause is widely used in natural and integrative healthcare.

It is also a phrase I think deserves careful explanation.

In complex conditions such as IBS, there may not be one root cause waiting to be discovered.

Instead, there may be a combination of predisposing factors, triggering events and ongoing influences that contribute to the person's symptoms.

For one individual, symptoms may have begun after a gastrointestinal infection.

For another, constipation and altered bowel motility may be prominent.

Someone else may experience pronounced food-related symptoms alongside increased visceral sensitivity.

And another person may notice that symptoms fluctuate significantly with sleep disruption, stress or changes in daily routine.

These differences matter.

When I take a clinical history, I am interested in questions such as:

• When did the symptoms first begin, and was there a recognisable event around that time?

• What does the person's usual bowel pattern look like?

• Are symptoms related to meals, bowel movements or particular times of day?

• Have there been changes in medication, supplements or dietary habits?

• Are there signs that warrant further medical investigation?

• What has already been tested, and what were the actual findings?

• How are symptoms affecting sleep, work, relationships, eating habits and quality of life?

These questions help build a more complete clinical picture.

They also help prevent us from treating every person with IBS as though they have the same underlying problem.

But individualised care should never become an excuse for unnecessary testing or speculative explanations.

I do not believe that every patient needs an extensive microbiome panel, multiple food intolerance tests or a complicated supplement protocol.

In fact, one of the most valuable parts of clinical reasoning is knowing which investigations are likely to change management and which may simply create more uncertainty.

Root-cause thinking, to me, is not about finding something wrong at all costs. It is about understanding the person, recognising relevant mechanisms and making informed decisions about their care.

What Meaningful IBS Care Actually Looks Like

One of the misconceptions surrounding IBS is that if we cannot identify one definitive cause, we cannot offer meaningful treatment.

But this is not true.

Evidence-based IBS care includes several approaches that can improve symptoms and quality of life.

Depending on the person's presentation, these may include dietary modification, soluble fibre, selected medications, gut-directed psychological therapies and support for relevant lifestyle factors.

For example, psyllium, a soluble fibre, can be helpful for some people with IBS.

A structured low-FODMAP approach may improve symptoms in appropriately selected patients, particularly when supported by a suitably trained dietitian.

Gut-directed cognitive behavioural therapy and hypnotherapy also have evidence supporting their use in IBS.

These treatments do not imply that symptoms are psychological or imagined.

They aim to influence the processes involved in gut–brain communication, pain perception and symptom-related distress.

Medications may also have an important role, particularly when constipation, diarrhoea or abdominal pain remains troublesome.

As a naturopath, I see nutrition, daily routines, sleep, movement and appropriate supportive therapies as potential parts of an individualised management plan.

Herbal and nutritional interventions may also be considered where there is suitable evidence, with attention to safety, medication interactions and the person's circumstances.

But not every natural treatment is effective simply because it is natural.

And not every supplement marketed for gut health has demonstrated benefits for IBS.

The evidence for probiotics, for example, varies substantially between strains, formulations and clinical outcomes. It is not appropriate to assume that any probiotic will improve symptoms or that every person with IBS needs one.

Likewise, repeated restrictive diets, unvalidated food sensitivity tests and prolonged antimicrobial protocols may create more problems than they solve.

Good care should be proportionate, evidence-informed and responsive to the individual.

Sometimes the most meaningful improvement comes from identifying a specific symptom mechanism.

Sometimes it comes from finding a dietary strategy that makes eating enjoyable again.

Sometimes it comes from addressing pain sensitivity or helping someone feel more confident navigating their symptoms.

And sometimes it involves accepting that there may not be one simple explanation while still finding ways to improve everyday life.

We do not need to know every contributing factor to provide effective care. But we should remain curious about the factors that matter.

The Problem With Stopping at the Diagnosis

There is something I think healthcare practitioners across all disciplines can agree on.

Patients deserve to understand their diagnosis.

Not simply to be given a name, but to understand what that name means, what is known about the condition, what remains uncertain and what their options are.

When someone receives an IBS diagnosis, they should not be left believing that their symptoms are insignificant because no structural disease was found.

Nor should they be told that everything must be caused by stress.

But equally, they should not be encouraged to believe that their diagnosis is invalid or that an undiscovered infection, toxin or microbial imbalance must be responsible.

Both extremes can be harmful.

IBS is a legitimate condition with recognised biological mechanisms and evidence-based management options.

What makes it challenging is that those mechanisms do not operate identically in everyone.

And this is precisely why individualised assessment matters.

A diagnosis can give us a useful framework.

It can guide appropriate investigations, inform treatment and help someone make sense of their symptoms.

But it should not replace clinical curiosity.

The diagnosis should guide the conversation, not end it.

Sev's Final Thoughts

If you have been diagnosed with IBS, I want you to know that your symptoms are real.

You do not need an abnormal scan, an alarming blood result or a visibly damaged intestine for your discomfort to be legitimate.

And you do not need to spend years searching for a hidden disease to justify what you are experiencing.

But I also believe you deserve more than a label you don't fully understand.

You deserve an explanation of what IBS is, what may be contributing to your symptoms, what has been appropriately ruled out and what evidence-based options are available to help you feel better.

As a naturopath, I approach digestive health with the understanding that the gut does not function in isolation.

Its relationship with the nervous system, immune system, diet, daily routines and wider physiology can influence how symptoms develop and persist.

That doesn't mean every case has a single discoverable root cause.

It means there is value in looking at the whole picture.

And perhaps this is where the title of this article comes full circle.

IBS isn't BS. But the idea that a diagnosis always tells us everything we need to know? That deserves questioning.

Because naming a condition is important.

Understanding the person experiencing it is just as important.

Sevim xx