Irritable Bowel Syndrome (IBS) Triggers, Prevention

Medically Reviewed on 3/24/2023

What is IBS (irritable bowel syndrome)?

This image shows the anatomy of the GI tract, including the small intestine, colon, and rectum.
The anatomy of the GI tract.

Irritable bowel syndrome (IBS) is a chronic relapsing gastrointestinal (mainly the large intestine or colon) disorder with signs and symptoms that may include:

IBS is a chronic condition that can be triggered by diet, medications, and/or by other conditions such as stress.

Some healthcare professionals categorize and term IBS into one of four categories:

  1. IBS-D (predominant symptoms is diarrhea)
  2. IBS-C (predominant symptom is constipation)
  3. IBS-M (mixed diarrhea and constipation)
  4. IBS-U (unclassified)

Not all healthcare professionals recognize these four categories.

Are stress and anxiety triggers for IBS?

Stress and anxiety may be triggers for IBS and the development of recurrent symptoms. Chronic stress experienced early in life (less than age 18) may increase the chances of developing the condition. Moreover, people diagnosed with IBS can have stress or anxiety-trigger symptoms, such as:

  • Diarrhea
  • Constipation
  • Abdominal bloating
  • Mucus defecation
  • Feelings of incomplete bowel movements

Are menstrual pain and IBS related?

Some studies show that many women with IBS have worse symptoms during their menstrual periods. Although the mechanism is not clear, some gastrointestinal cells have receptors for estrogen and progesterone so changes in the hormone levels during the menstrual cycle may trigger increasing IBS symptoms. Women are twice as likely to develop IBS as men.

What foods in the diet trigger constipation in IBS?

Any foods or fluids that tend to dehydrate a person are likely to trigger constipation in people with irritable bowel syndrome.

Foods that may promote constipation should be avoided in an IBS diet and include:

  • Chocolate
  • Dairy products such as milk and cheese (particularly those that contain lactose)
  • Red meat
  • Unripe bananas
  • Items that contain caffeine if you are slightly dehydrated.
  • Coffee, carbonated drinks, and alcohol may lead to dehydration and constipation in IBS patients (and other people, too).

Foods that help prevent constipation in IBS

Foods that help prevent constipation and should be included in an IBS diet include:

  • Prunes
  • Various types of beans
  • Whole grain breads like rye bread
  • Pears and fruits like kiwi
  • Vegetables that will help boost fiber intake

What foods in the diet trigger diarrhea in IBS?

Several foods may play a role in developing diarrhea in people with IBS. Major categories of foods that may trigger IBS are those that contain fats (fatty meats, fatty dairy products, for example). Each individual is slightly different and may respond differently to food types. Consequently, dietitians and health care professionals who treat people with IBS often suggest that they keep a journal or diary to track those foods that cause diarrhea.

  • Some foods that trigger diarrhea do so because they are ingested in large quantities; for example, a bite of a banana may not cause diarrhea, but eating a whole banana may trigger diarrhea in some people with IBS.
  • Other foods that contain high levels of fructose, artificial sweeteners, high FODMAP foods, and fried foods may also trigger diarrhea.
  • Broccoli, onions, cabbage, and large helpings of beans may produce gas and increase the discomfort of diarrhea.

Probiotics may help reduce the symptoms of diarrhea and gas in some individuals.

What prescription or OTC drugs trigger IBS?

Some drugs can trigger IBS symptoms resulting in colonic spasms, constipation, and/or diarrhea. Such drugs include:

Consequently, patients with the condition should check the ingredients, both active and inactive, for the presence of sorbitol as sorbitol is often listed as an "inactive" ingredient.

SLIDESHOW

IBS - Irritable Bowel Syndrome: Symptoms, Diet, Treatment See Slideshow

What are the other IBS triggers?

Other triggers of IBS are variable and differ from person to person. However, some other common triggers include:

  • Lack of exercise
  • Eating food too quickly
  • Eating while under some other stress such as driving or working
  • Eating foods that are very hot or cold
  • Chewing gum

Keep a journal and record the symptoms and the activities you are doing when symptoms develop. This can help you determine your triggers for any symptoms. Researchers also suggest that changes in hormone levels and/or other acute illnesses such as infectious diarrhea may also trigger symptoms.

How can I prevent IBS triggers?

There are many different ways to help prevent triggering IBS symptoms such as:

  • Eat a balanced diet with a moderate amount of fiber.
  • Avoid extremes of food temperatures (very hot or cold foods).
  • Do not eat while experiencing anxiety or under stressful conditions (for example, while working or driving).
  • Avoid foods and drinks that may cause dehydration or diarrhea.
  • Keep a journal to help identify those foods that do or do not trigger symptoms.
  • Try biofeedback, exercise, meditation, or yoga to reduce anxiety.
  • Discuss medications you are taking that may be triggering symptoms with your doctor.
  • Avoid those foods and drinks that are likely to increase or trigger symptoms.
  • Avoid foods that increase intestinal gas (some legumes and vegetables like broccoli, cauliflower, cabbage, and Brussels sprouts).
  • Talk to your doctor or health care professional about taking probiotics.
Medically Reviewed on 3/24/2023
References
Abraczinskas, D. "Patient information: Gas and bloating (Beyond the Basics)." UpToDate. February 2019. <https://www.uptodate.com/contents/gas-and-bloating-beyond-the-basics>.

National Institute of Diabetes and Digestive and Kidney Diseases. "Irritable Bowel Syndrome (IBS)." <https://www.niddk.nih.gov/health-information/digestive-diseases/irritable-bowel-syndrome>.

Wald, A. "Patient information: Irritable bowel syndrome (Beyond the Basics)." UpToDate. February 2019. <https://www.uptodate.com/contents/irritable-bowel-syndrome-beyond-the-basics>.