How Diet Affects People Who Have IBS

Anyone with irritable bowel syndrome (IBS) knows of at least one or two foods that contribute significantly to their symptoms. However, several other unidentified foods may also trigger IBS symptoms, making mealtime challenging. Unfortunately, no one diet will work for everyone with IBS, but there are some guidelines that may help.

Eating several smaller meals during the day, rather than three large ones, is one tactic that may help reduce symptoms. Some people with IBS find that large meals may result in cramping and diarrhea. Additionally, many people find it helpful to keep their meals low in fat and high in carbohydrates such as whole-grain bread, pasta, rice, fruits, vegetables, and cereals. A low fat, high protein diet may also help with pain experienced after eating.

Bowl of oatmeal with fresh sliced figs
lily_rochha / Getty Images

Common Trigger Foods

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

Fiber

Soluble fiber has several benefits that may also reduce symptoms of IBS. Fiber may help prevent spasms because it keeps the colon somewhat distended. Fiber absorbs water, which helps keep stools from being too hard and therefore difficult to pass, which could lead to constipation. Enough fiber should be added to the diet so that stools are soft and passed painlessly and easily. Initially switching to a high-fiber diet may increase gas and bloating, but these symptoms should decrease as the body becomes adjusted to it. For most people, this transition period may last a few weeks.

Sources of Soluble Fiber

  • Barley
  • Brown rice
  • Currants
  • Dried beans
  • Figs
  • French bread
  • Fresh peas
  • Methylcellulose (Citrucel)
  • Oat bran
  • Oatmeal
  • Pasta
  • Prunes
  • Psyllium husks (Benefiber)
  • Raisins
  • Rice
  • Sourdough bread
  • Soy

Foods That May Cause Gas

  • Bananas
  • Beans
  • Broccoli
  • Brussels sprouts
  • Cabbage
  • Cauliflower
  • Garlic
  • Leeks
  • Nuts
  • Onions
  • Raisins

Food Sensitivities

It has been suggested that some people with IBS have food sensitivities. Food sensitivity is different than a true food allergy, so an intolerance will not be detected during an allergy test. Some of the more common offenders have been identified as:

  • Sorbitol (a sugar substitute)
  • Fructose (found in fruit juice and dried fruit)
  • Lactose (found in milk)
  • Wheat bran

Lactose Intolerance

Lactose intolerance is a common condition that is the result of the body's inability to digest lactose, or milk sugar. Symptoms include gas, bloating, and sometimes pain. If lactose intolerance is suspected, avoidance of milk and milk products (cheese, ice cream, and butter) should reduce symptoms. When milk products are reduced, care should be taken that enough calcium is added to the diet through either eating foods high in calcium or taking a calcium supplement.

Probiotics

Probiotics refer to the "good bacteria" in the body. They are most commonly associated with the the gut, and the overall role of probiotics is to help maintain balance in the body. Your body naturally has probiotics, but this good bacteria also naturally occurs in certain foods, such yogurt and fermented foods. Probiotics can also be purchased over-the-counter in supplement form.

Some research has shown that people with IBS have an imbalance in their gut flora - including a tendency to have lower amounts of Lactobacillus and Bifidobacterium and higher levels of harmful Streptococcus, E. coli and Clostridium. As such, researchers have investigated the utility of probiotics in helping to alleviate symptoms of IBS.

Importantly, while research has shown probiotics can have a positive effect on symptoms for people with IBS, there isn't enough evidence for doctors to officially recommend probiotics as a treatment option. The American Gastroenterology Association, in its 2020 clinical practice guidelines, only recommends probiotics for symptomatic children and adults with IBS in the context of a clinical trial.

Food Diaries

A food diary may help with identifying the offending foods. Any food sensitivity should be investigated with the help of a nutritionist or a doctor. Sensitivities might be overlooked without the help of a trained professional.

IBS Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

Doctor Discussion Guide Man

A Word From Verywell

Discovering what foods will help or harm IBS can be a challenge. At times it will be difficult to follow a strict diet, especially if other people are not sensitive to your needs (you know them--they tell you "it's all in your head"). It may be hard for you and the people around you to accept, but it may be even worse to deal with an IBS attack caused by trigger foods or heavy meals.

2 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. Noh Hong S. and Rhee PL. Unraveling the ties between irritable bowel syndrome and intestinal microbiota. World J Gastroenterol. 2014 Mar 14; 20(10): 2470–2481. doi: 10.3748/wjg.v20.i10.2470

  2. Su G, Ko C, Bercik, P, ET al. AGA Clinical Practice Guidelines on the Role of Probiotics in the Management of Gastrointestinal Disorders. Gastroenterology. June 9 2020. doi:https://doi.org/10.1053/j.gastro.2020.05.059

Additional Reading

By Amber J. Tresca
Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.