Irritable bowel syndrome (IBS) is a disorder that causes frequent abdominal symptoms, including diarrhea, constipation, bloating, and cramps.

While the exact cause of IBS is unclear, researchers believe that changes to a person’s lifestyle and diet can significantly affect the condition.

IBS and inflammatory bowel disease (IBD) are two different conditions. IBS refers to a group of symptoms that point to a problem in bowel function. IBD refers to two diseases; Crohn’s disease and ulcerative colitis, which involve an abnormal immune response and chronic inflammation.

Some people with IBS find that certain foods worsen their symptoms and that eliminating these foods from the diet provides relief.

This article offers general dietary advice for people with IBS and lists specific foods to avoid.

Learn more about the signs and symptoms of IBS here.

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Dietary recommendations for IBS often include the following:

  • Eat more soluble fiber: This makes stool easier to pass, while insoluble fiber can aggravate IBS symptoms.
  • Eliminate gluten, lactose, or both: Doing so could help ease symptoms.
  • Limit hard-to-digest carbohydrates: Some foods contain high levels of these carbs, which doctors call FODMAPS (fermentable oligo-, di-, and monosaccharides and polyols).

Research indicates that consuming high-FODMAP foods may worsen symptoms of IBS, such as:

However, some people with IBS can tolerate certain quantities of FODMAP-containing foods. This is because food can either be high or low in FODMAPs based on serving sizes.

The MONASH University FODMAP app is a helpful database of foods that lists their FODMAP level based on serving sizes. For example, it considers a 2.8 ounce (oz) serving of avocado as high in FODMAPs and a 1-oz serving as low in FODMAPs.

This means that although people with IBS may react to a larger portion of a FODMAP-containing food, they may tolerate a smaller portion.

A doctor or dietitian can help a person make dietary changes aimed at resolving IBS symptoms.

To identify triggers, they may recommend eliminating certain foods, then reintroducing them one by one to determine which ones cause symptoms. They may also ask a person to keep a food journal to note down when symptoms occur.

Learn more about the elimination diet and other diet options for IBS.

Although most people with IBS have different food triggers, some food groups or products are more likely to cause IBS symptoms than others.

The following can trigger symptoms of IBS:

  • fruits: apples, apricots, blackberries, mangoes, cherries, nectarines, peaches, plums, ripe bananas, watermelon, and pears, whether whole or in juice
  • vegetables: artichokes, cabbage, asparagus, cauliflower, garlic, mushrooms, onions, soybeans, sweetcorn, green peas, snap peas, and snow peas
  • pulses: lentils, beans, and chickpeas
  • dairy products: milk, ice cream, sour cream, and cottage cheese, unless they are lactose-free
  • insoluble fiber: bran, whole grains, nuts, corn, and the skins of fruits and vegetables
  • wheat and rye products: bread and other baked goods, as well as products, such as sauces, that contain wheat flour for thickening
  • sweeteners: honey, high fructose corn syrup, and artificial sweeteners, such as sorbitol, maltitol, or xylitol

A person may also want to avoid resistant starches common in whole grains, partially baked bread, and processed foods, such as potato chips.

These reach the large intestine almost undigested, and during digestion in the colon, fermentation occurs, producing gas.

Other products that may cause or worsen IBS symptoms include:

  • alcohol
  • very fatty foods, such as fried foods
  • spicy foods
  • gluten-containing foods
  • dairy products
  • high sugar foods

However, keep in mind that the foods and drinks that trigger IBS symptoms vary from person to person. It is essential for anyone with this condition to identify their triggers.

Learn more about what foods to avoid with IBS.

While eliminating foods that cause or worsen IBS symptoms, a person may benefit from adding the following to their diet:

  • Low-FODMAP fruits: These include blueberries, cantaloupe, grapes, oranges, kiwis, and strawberries.
  • Low-FODMAP vegetables: These include carrots, eggplant, green beans, spinach, squash, and sweet potatoes.
  • Dairy alternatives: Lactose-free products or rice, soy, almond, or oat alternatives may be a good choice.
  • Yogurt: Some research indicates that probiotics found in yogurt may improve IBS symptoms.
  • Soluble fiber: Found in oats, psyllium, and some fruits and vegetables, this type of fiber helps regulate bowel movements.
  • Sweeteners: Maple syrup without high fructose corn syrup or stevia can replace sweeteners ending in “-ol.”

While it may not be possible to eliminate all the IBS triggers in a recipe, reducing their quantities can help.

Learn more about the FODMAP diet and whether it works for IBS here.

Going to a restaurant can be stressful for a person with IBS, but the following strategies can help.

First, be sure to read the menu carefully. Check for ingredients that may cause symptoms and ask:

  • What exactly does the dish contain?
  • How much of a triggering ingredient is in the dish?
  • Is it possible to prepare the dish without the ingredient?

Some people prefer to check the menu online and inquire ahead of time.

Also, it can help to:

Ask for a gluten-free or lactose-free menu: Some restaurants have them.
Check the base of soups: Broth-based soups are less likely to contain dairy products, such as cream, milk, or cheese, which may cause symptoms in some people with IBS.
Find out what vegetable dishes contain: Check the ingredients in a vegetable medley or stir-fry.
Ask about added ingredients: Hamburgers, for example, may contain breadcrumbs or onions, both of which can worsen IBS symptoms.
Opt for grilled (not fried) foods: Grilled foods contain less fat and can cause less stomach discomfort.
Bring a favorite dressing: Some people take along condiments from home, as commercial dressings and sauces contain additives that aggravate their symptoms.

It may be worth researching a restaurant’s options before booking a table.

Learn more about what gluten-free means here.

Many people with IBS find that cooking food at home with fresh ingredients is a good way to avoid symptoms.

Other tips that may help include:

  • eating regularly and avoid delaying or missing meals
  • eating smaller meals
  • taking time when eating
  • eating no more than 3 servings of fresh fruit a day
  • limiting the intake of tea and coffee to 3 cups per day
  • drinking plenty of water
  • eating more protein than carbohydrates

Every person with IBS is different, which is why it’s important to develop a nutritious eating plan tailored to your specific needs.

Learn more about treatment options for IBS here.

IBS is a common gastrointestinal disorder that can cause significant discomfort. A person’s diet can trigger or worsen symptoms.

Identifying and avoiding triggering foods and drinks can help a person with IBS enjoy their meals at home or eating out.