Irritable bowel syndrome (IBS) is a disorder of the intestines that causes abdominal pain or discomfort. The pain may occur alone or along with constipation or diarrhea. Other symptoms include bloating, mucus in stools, or a sense that you have not completely emptied your bowels.

In irritable bowel syndrome, you have symptoms in the digestive tract but doctors can find no change in physical structure, such as inflammation or tumors.

It is not clear what causes irritable bowel syndrome, and the cause may be different for different people. Some ideas for what causes IBS include problems with the way signals are sent between the brain and the digestive tract, problems digesting certain foods, and stress or anxiety. People with IBS may have unusually sensitive intestines or problems with the way the muscles of the intestines move.

Managing stress and changing your diet are the main treatments for the condition. Medicines may be used to treat severe symptoms that interrupt daily activities.

Continue to Why?

Many people find that their irritable bowel syndrome (IBS) symptoms become worse after they eat. Sometimes certain foods make symptoms worse.

No particular foods cause everyone with IBS to have symptoms. Doctors do not advocate a particular diet to manage symptoms. But through trial and error, many people find that they feel better when they stop eating certain foods. For some people, certain foods may cause them to have symptoms of abdominal pain, constipation or diarrhea, and bloating. A high-fiber diet may reduce symptoms, particularly for people who have constipation.

Continue to How?

Although there is no particular diet to follow, you can manage your irritable bowel syndrome (IBS) by limiting or eliminating foods that may bring on symptoms, particularly diarrhea. In general, you can change your diet based on whether your main symptom is constipation or diarrhea.

You also can keep a diary of what you eat and how it affects you. In addition, it helps to make sure that mealtimes are relaxing, which may prevent stress from bringing on symptoms.

Following a diet to reduce constipation

Taking the following steps may reduce your constipation:

• Add fiber to your diet. Fiber will absorb water and add bulk to the large intestine, making bowel movements easier and more frequent than you usually experience. Eat high-fiber foods such as fresh fruits (raspberries, pears, apples), fresh vegetables (peas, brussels sprouts), wheat bran, whole-grain breads and cereals, and beans (such as kidney, pinto, and garbanzo). Increase the amount of fiber in your diet slowly to avoid excess gas.
• Drink plenty of water. Also be sure to drink plenty of fluids, enough so that your urine is light yellow or clear like water. Fiber absorbs water, so drinking enough water will help keep stools soft.
• Get regular exercise. Regular, gentle exercise such as walking, cycling, or swimming helps maintain bowel regularity.

If it is difficult to eat enough high-fiber foods, try using a nonprescription fiber supplement or bulking agent that contains crushed psyllium seed or methylcellulose. Examples include Citrucel, FiberCon, and Metamucil. Start with a small dose and very slowly increase the dose over a month or more. These products are different from laxatives because they do not irritate the lining of the intestine. They are safe for long-term use. To increase their effectiveness, take fiber supplements at the same time you eat. Although you may find the taste or texture unpleasant, most people get used to them over time, and the safety and effectiveness may be worth the inconvenience. Use laxatives (for example, milk of magnesia or bisacodyl—such as Dulcolax) only when recommended by your doctor.

Not all experts agree that eating more fiber will help reduce or prevent your symptoms of IBS. For some people who have IBS, eating more fiber may actually make some symptoms worse, such as bloating. Check with your doctor before increasing the amount of fiber in your diet. Add fiber gradually so your body can adjust to the change; if you do not, you may experience bloating.

Following a diet to reduce diarrhea

You may be able to reduce diarrhea if you limit or eliminate the following foods and beverages:

• Alcohol
• Caffeine, which is found in coffee, tea, cola drinks, and chocolate
• Nicotine, from smoking or chewing tobacco
• Gas-producing foods, such as beans, broccoli, cabbage, and apples
• Dairy products that contain lactose (milk sugar), such as ice cream, milk, cheese, and sour cream
• Foods and drinks high in sugar, especially fruit juice, soda, candy, and other packaged sweets (such as cookies)
• Foods high in fat, including bacon, sausage, butter, oils, and anything deep-fried
• Sorbitol and xylitol, artificial sweeteners found in some sugarless candies and chewing gum

You may try eliminating foods or beverages one at a time to see whether symptoms improve. If a specific food does not seem to be related to symptoms, there is no need to continue avoiding it.

You might want to consult a registered dietitian before eliminating foods from your diet. A dietitian can help you plan a diet to minimize symptoms while maintaining good nutrition.

Keeping a food diary

Some people with IBS use a daily food diary to keep track of what they eat and whether they have any symptoms after eating certain foods. The diary also can be a good way to record what is going on in your life. Stress plays a role in IBS: If you are aware that particular stresses bring on symptoms, you can try to reduce those stresses.

Maintaining a pleasant mealtime environment

Try to maintain a pleasant environment when you eat. This may reduce stress that can make symptoms likely to occur. Give yourself plenty of time to eat, rather than eating on the go. Chew your food slowly. Try not to swallow air, which can cause bloating.

Continue to Where?

Be sure to talk to your health professional before beginning a plan to reduce or eliminate certain foods from your diet. It's fine to eliminate beverages such as alcohol or caffeine or items such as sugarless gum or candy, but be careful before removing entire groups of vegetables or fruits.

You may be able to eat some fruits and vegetables but not others. Your health professional may recommend that you consult a registered dietitian to help you plan a nutritious menu that helps reduce your symptoms.

If you would like more information on irritable bowel syndrome (IBS), the following resources are available:

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