What You Need to Know About Irritable Bowel Syndrome (IBS)

A salad on a table

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Irritable bowel syndrome (IBS) is classified as a functional gastrointestinal disorder. This is because when tests such as a colonoscopy are done, no obvious signs of a disease, such as ulcers or inflammation, are found. It's for this reason that IBS is often diagnosed only after other possible digestive disorders and diseases that cause pain or diarrhea have been ruled out.

IBS is often misdiagnosed or misnamed as colitis, mucous colitis, spastic colon, inflammatory bowel disease, or spastic colon. These are incorrect terms and they keep cropping up, even though IBS is now a recognized and treatable condition.

Affecting 25 to 55 million people in the United States, IBS is the cause of 2.5 to 3.5 million yearly visits to physicians. It's estimated that 20 percent to 40 percent of all visits to gastroenterologists are due to the symptoms of irritable bowel.

A bowel movement occurs when muscles in the bowel contract, and in most people, this is something that happens a few times a day. The theory is that for people with IBS, the muscles are more sensitive, and being exposed to certain foods or stresses can cause more contractions. Eating a salad or drinking a coffee may not have much of, or any, an effect on most people, but for a person with IBS, these things could cause symptoms such as pain, bloating, and diarrhea.


The symptoms of IBS can include:

  • Gas
  • Pain
  • Bloating
  • Nausea
  • Vomiting
  • Mucus in the stool
  • Constipation
  • Diarrhea

Cramps are often relieved by a bowel movement, but some people with IBS may have cramps and be unable to pass anything. The severity of IBS symptoms varies and may be described as anything from a mild annoyance to debilitating.

Blood in the stool, fever, weight loss, vomiting bile, and persistent pain are not symptoms of IBS and may be the result of some other problem.


Many people with IBS describe that symptoms frequently occur shortly after, or even during, meals. Fatty foods, alcohol, caffeine, and gas-producing foods (such as broccoli or beans) have regularly been things that are pinpointed as causing IBS symptoms. However, it can be difficult for some people to track down which particular foods can trigger their IBS.

Making the issue even more complicated, not every person with IBS will have symptoms after eating the same foods. The range of triggers is unique to each person, although there are many triggers that are common among people with IBS. Symptoms can also come and go even after eating the same foods. Something that was fine to eat last week may start causing symptoms today—or the reverse.

Keeping a food and symptom diary is a good way to trace foods that lead to IBS symptoms. Starting with a bland diet of "safe foods" and gradually adding new food each day can also help in the search for specific food triggers. The food diary can then be discussed with a doctor or dietitian for help in treatment.

Common Trigger Foods in IBS

Foods that may trigger symptoms of IBS in some people include:

  • Alcohol
  • Artificial sweeteners
  • Artificial fat (Olestra)
  • Carbonated beverages
  • Coconut milk
  • Coffee (even decaffeinated)
  • Dairy
  • Egg yolks
  • Fried Foods
  • Oils
  • Poultry skin and dark meat
  • Red meat
  • Shortening
  • Solid chocolate


For constipation, a doctor may prescribe laxatives or fiber supplements such as Metamucil. Fiber supplements help with both constipation and diarrhea. They bulk up the stool in cases of diarrhea, and also make it easier to pass in the case of constipation. Laxatives can be habit-forming and should be used under the close supervision of a physician. Eating enough fiber in the diet may also help some people with IBS to reduce their symptoms. Often there is some trial and error in finding the right types of fiber and how much to eat each day.


Treatment for IBS can include changes to diet, lifestyle, stress reduction, and medications. Often, a combination of two or more of the above will help to provide the most relief. There is still much that is not understood about IBS, so it may take some time, and some experimentation with different therapies, to achieve good results.


Anti-spasmodic drugs or tranquilizers may be used to stop the over sensitivity of the muscles in the bowel. Stopping the spasms in the bowel can reduce pain and the feeling of urgency. Anti-diarrhea medications may also be used to slow down frequent, watery stools.

Lifestyle Changes

Smaller portions at mealtimes may help to prevent bloating and cramping. Instead of three large meals every day, five smaller meals may also help in reducing symptoms. Eating a healthy diet, drinking plenty of water, and getting daily exercise is also helpful in reducing IBS symptoms. These changes can also contribute to an overall healthy lifestyle.

Stress Reduction

Relaxation training, in addition to medical therapy, can also help to reduce symptoms. It is important to note that stress is not the cause of IBS, but as with any disease or disorder, stress can cause the symptoms of IBS to worsen.

IBS is not believed to lead to ulcerative colitis, Crohn's disease, or cancer.

A Word From Verywell

The good news about IBS is that it is increasingly being seen under a new light. People with this common disorder can discuss symptoms with health care professionals without being told: "it's all in your head." In the last 20 years, much research has been done to discover more about IBS and other gastrointestinal disorders. Treatment for IBS is better now than ever, but more research and awareness is needed to raise the quality of life for those who suffer from IBS.

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