Irritable bowel syndrome - How common is irritable bowel syndrome?
BMJ Group Medical Reference
Irritable bowel syndrome (IBS) is very common.
In the UK, more than 2 in 10 women and 1 in 10 men have IBS.  A study of nearly 5,000 people found that over 15 in 100 people have the condition. 
However we're not certain about these numbers. This is because doctors diagnose IBS in different ways. The estimates of how many people have it vary depending on how researchers diagnose it. And most people who have symptoms of IBS seem to cope on their own rather than getting help from their doctor. Although IBS is very common, only about 5 in 100 people see a doctor because of it.
Unlike lots of other long-term conditions, IBS tends to appear when people are young or middle-aged, rather than older. Symptoms begin before the age of 50 in half of all people who are diagnosed with IBS. About 4 in 10 people with IBS are aged between 35 and 50.
Children can get IBS too. Lots of people can trace the start of their symptoms back to childhood. Symptoms of IBS have been found in 6 in 100 12 to 13 year olds, and in 14 in 100 15 to 16 year olds.
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