Irritable Bowel Syndrome Facts and Statistics: What You Need to Know

It is estimated that 10%–15% of adults in the United States have irritable bowel syndrome (IBS).  It's also diagnosed in about twice as many females as males.

IBS is a functional gastrointestinal (GI) disorder, meaning there are problems with how the brain and gut work together. It is characterized by a group of symptoms that include abdominal pain and changes to bowel movements, which can disrupt daily life.

This article will highlight important facts and statistics you should know about irritable bowel syndrome.

Person experiencing abdominal pain from IBS

LaylaBird / Getty Images

Irritable Bowel Syndrome Overview

IBS is a disorder of the gut-brain interaction. People with IBS have a more sensitive gut, which changes how the muscles in the bowel contract.

This can lead to symptoms such as abdominal pain, bloating, distension, and flatulence, as well as changes in bowel movements, including constipation, diarrhea, or both. Symptoms can come and go and range from debilitating for some people to only mild or moderate for others. 

There is no cure for IBS. However, medication, diet, and lifestyle changes can often manage symptoms.

How Common Is Irritable Bowel Syndrome?

IBS is one of the most common disorders healthcare providers treat since it affects 10%–15% of adults in the United States. However, only 5%–7% of U.S. adults have been formally diagnosed. It’s estimated that 5%–10% of the global population has IBS, as well.

Irritable Bowel Syndrome by Ethnicity

Data relating to IBS and ethnicity are very limited. One older U.S. study reported that IBS is more commonly diagnosed in White people than Black people.

According to the American College of Gastroenterology, IBS appears to affect people from all over the world the same. More research is needed to fully determine the impact IBS has on people of individual cultures and ethnicities.

Irritable Bowel Syndrome by Age and Gender

More women than men are diagnosed with IBS. About 2 times as many women in the United States are diagnosed with IBS than men. It is unclear what leads to this disparity.

IBS is more likely to be diagnosed at a younger age—prior to age 50—than over age 50. However, it can affect people of all ages, from children to older adults.

Causes of Irritable Bowel Syndrome and Risk Factors

Experts do not fully understand what causes IBS. It appears to be complex, though it is thought to have to do with how sensitive the gut is to certain stimuli, how it interacts with the brain and nervous system, and how the bowels work and contract in general.

In addition, people with IBS may often have symptoms triggered or worsened by certain foods, life stressors, or other medical conditions.

Sometimes IBS is triggered by an infection in your gastrointestinal tract or by trauma. Some research suggests you might be more likely to develop IBS due to genetics.

Screening and Early Detection

There is no standard screening for IBS in the general population. Typically people are screened for IBS after having diarrhea and/or constipation that comes and goes, stomach pain or distension, or bloating.

A healthcare provider will examine you, ask about your symptoms, and may ask for a stool sample or blood tests to help rule out other conditions. 

Many people experience symptoms for years before receiving a formal diagnosis of IBS. This is due to various reasons, such as ruling out other possible medical problems,

According to the International Foundation for Functional Gastrointestinal Disorders, nearly 2,000 people with IBS reported in a survey that they didn't receive a diagnosis of IBS until over 6.5 years after they first started having symptoms.

Being an advocate for yourself with your healthcare team and continuing to press for identification of what's causing your symptoms can help you receive the appropriate diagnosis sooner rather than later. This can help with the overall management of your IBS, allowing you to experience quality of life.


Irritable bowel syndrome (IBS) is a disorder of the gut-brain interaction that causes gastrointestinal (GI) symptoms such as abdominal pain, bloating, constipation, and/or diarrhea. Around 10%–15% of the U.S. adult population is thought to have IBS, with women being diagnosed more often than men. 

The exact cause of IBS is unknown. However, experts believe it has to do with gut sensitivity and how the gut interacts with the brain and nervous system.

Working with your healthcare team can help you identify your IBS triggers and find a treatment plan to best help you manage and improve your symptoms.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American College of Gastroenterology. Irritable bowel syndrome.

  2. Kim YS, Kim N. Sex-gender differences in irritable bowel syndrome. J Neurogastroenterol Motil. 2018;24(4):544-558. doi:10.5056/jnm18082

  3. IFFGD. IBS facts and statistics.

  4. Black CJ, Ford AC. Global burden of irritable bowel syndrome: trends, predictions and risk factors. Nat Rev Gastroenterol Hepatol. 2020;17(8):473-486. doi:10.1038/s41575-020-0286-8

  5. National Institute of Diabetes and Digestive and Kidney Diseases. Definition and facts for irritable bowel syndrome

  6. National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms and causes of irritable bowel syndrome.

By Brittany Poulson, MDA, RDN, CD, CDCES
Brittany Poulson, MDA, RDN, CDCES, is a registered dietitian and certified diabetes care and education specialist.