What is inflammatory bowel disease?
You might have heard of inflammatory bowel disease, often shortened to IBD. But what is it? How is it different to other conditions such as irritable bowel syndrome (IBS)? Here I answer some common questions about IBD including what the symptoms are and how it’s diagnosed.

What is inflammatory bowel disease?
Inflammatory bowel disease (IBD) is the name for a group of inflammatory conditions affecting the colon (large intestine) and small intestine. It’s when the body’s own immune system starts attacking healthy cells in the intestines, causing inflammation (swelling) and other damage that needs treatment to manage it.
It’s still unclear what causes IBD. There is more than one type of IBD. The two main types are Crohn’s disease and ulcerative colitis (also called colitis).
What are IBD symptoms?
Not everyone will have the same symptoms, which can range from mild to severe. But common symptoms of IBD include:
- stomach cramping or pain
- diarrhoea (runny poo)
- blood or mucus in your poo
- change in bowel movements, including constipation
- feeling very tired
- losing your appetite
- losing weight
- anaemia (not having enough iron in your blood)
How is IBD diagnosed?
If you think you might have IBD symptoms speak to a doctor. They will ask you questions about your symptoms, and they might suggest you have some tests. These tests might include:
- a blood test
- a stool (poo) sample
- tests that use a camera to look inside your gut, such as an endoscopy, flexible sigmoidoscopy or colonoscopy
- imaging scans, such as ultrasound, CT and MRI
What’s the difference between Crohn’s disease and colitis?
Both Crohn’s disease and colitis cause inflammation in your digestive system. Crohn’s disease, often known simply as Crohn’s, can cause different parts of your gut to become inflamed. Usually, it affects the small intestine and large intestine. Colitis only causes your large bowel (also called your colon) to become inflamed. It can also cause ulcers to form in your colon.
In certain cases when diagnosing IBD, it might be hard to know which of the two diseases you have.
Is IBD curable?
IBD can’t be cured, but there are treatments to help you live with the condition. IBD treatment can include:
- medicines to reduce inflammation in your gut
- medicines to control your immune system
- changes to your diet and lifestyle
- surgery to remove part of your gut
Your doctor can advise what treatment would be best for you.
Most people have weeks or years where they don’t experience symptoms, or their symptoms are not as severe. The periods of time where your symptoms come back and you feel unwell are called flare-ups. These can last anywhere from a few days to a few months. Some people go for years without flare-ups.
What diet is best for IBD?
There isn’t a specific diet to follow if you have IBD. The most important thing is to eat a healthy balanced diet and stay hydrated. Some people find that very spicy foods or food containing a lot of fibre make their symptoms worse. Keep a food diary to help you track if certain foods trigger your symptoms. You should speak to a dietitian before cutting out any foods to make sure you’re getting all the nutrients you need from your diet.
Sometimes during a flare-up, you might need to follow special dietary advice. Your nurse or doctor will let you know when you need to follow this diet and a dietitian can support you on how exactly to do this. They might also recommend you take supplements.
What is the difference between IBD and IBS?
Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are very different conditions. Irritable bowel syndrome (IBS) is not a disease. Instead, it’s a group of symptoms.
Even though they are different conditions, IBD and IBS do share some of the same symptoms. And you can have both conditions at the same time.
Is IBD worse than IBS?
While IBS can be difficult to live with, it doesn’t lead to damage of the bowel that’s seen in IBD. It doesn’t cause inflammation or damage to your gut and there isn’t a test that can tell you if you have it.
IBS is much more common than IBD. In the UK, just under 1 in every 100 people have Crohn’s disease or colitis. But around 15 in every 100 people are thought to have IBS.
What conditions share symptoms with IBD?
As well as IBS, other conditions that might have similar symptoms to IBD include:
So, if you’re having digestive symptoms, it’s important to see a GP or gastroenterologist to investigate further and help improve your symptoms.
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Sources Sources
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