What Is IBS? A Plain-English Guide to Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic gut condition that affects how your digestive system works. It's not a disease in the traditional sense — there's no inflammation, no structural damage, nothing that shows up on a scan. Which is partly why it's so frustrating to be diagnosed with.

You feel genuinely terrible. Your scans come back clear. Your doctor says you have IBS. And then... not much happens.

What actually causes IBS?

The honest answer is: we don't fully know. IBS is thought to involve a combination of factors including:

• Gut-brain communication problems — the signals between your gut and nervous system are misfiring, making your gut hypersensitive to normal digestion
• Altered gut motility — things move too fast, too slow, or unpredictably
• Gut microbiome imbalances — the balance of bacteria in your digestive tract may be disrupted
• Post-infectious changes — IBS often develops after a bout of gastroenteritis or food poisoning
• Stress and anxiety — not as the "cause," but as a real physiological trigger that worsens symptoms

The main types of IBS

IBS is usually classified by your predominant bowel pattern:

• IBS-D (diarrhoea predominant) — frequent loose stools, urgency, cramping
• IBS-C (constipation predominant) — infrequent, difficult bowel movements
• IBS-M (mixed) — alternating between diarrhoea and constipation
• IBS-U (unsubtyped) — doesn't fit neatly into the above

Many people find their subtype shifts over time, which adds to the confusion.

The role of food

Food doesn't cause IBS, but it's one of the most reliable triggers for symptoms. The problem is that food triggers vary enormously from person to person. What wrecks one person's gut has no effect on another's.

Common food-related triggers include:

• High-FODMAP foods (fermentable carbohydrates that pull water into the gut and ferment rapidly)
• Fatty or fried foods
• Caffeine and alcohol
• Gluten (in some people — separate from coeliac disease)
• Dairy

The only reliable way to identify your specific triggers is to track what you eat alongside your symptoms — consistently, over enough time to see patterns.

What you can actually do

There's no cure for IBS, but most people can get their symptoms under significant control through:

1. Identifying and reducing food triggers through structured tracking and elimination
2. Managing stress — this has a direct, physiological effect on gut symptoms
3. Gut-directed therapy — a growing evidence base for hypnotherapy and CBT for IBS
4. Medication — various options for symptom relief depending on your subtype
5. Working with a specialist dietitian — particularly for low-FODMAP guidance

The tracking step is where most people get stuck — and it's where we can help. Our IBS & Food Sensitivity Tracker is designed to make this process as simple and actionable as possible.