People with irritable bowel syndrome (IBS) have abdominal pain and diarrhea and or constipation. A diet low in FODMAPs, which are types of carbohydrates in foods, may help some people with IBS manage their symptoms.
FODMAP stands for fermentable oligo-saccharides, disaccharides, mono-saccharides, and polyols. These are types of short chain carbohydrates--sugars, starches, and fiber--found in a variety of foods that are poorly absorbed in the small intestine and absorb water and ferment in the colon.
The following types of carbohydrates are FODMAPS:
Fructans - found in garlic, onions, and wheat
Fructose - found in fruits, honey, and high fructose corn syrup
Galactans - found in beans and legumes
Lactose - found in dairy
Polyols - found in fruits with pits, such as apples, avocados, or cherries and in sugar alcohols
Most people can eat high-FODMAP foods without any problem. In fact, many of these foods can encourage good bacteria to grow in the intestines. However, people with IBS may tend to be more sensitive to foods high in FODMAPs.
FODMAPS are not easily absorbed in the small intestine. They move through slowly, and take on water. In the bowel, bacteria rapidly ferment the FODMAPs, causing gas. The excess gas and water can cause bloating, pain, and diarrhea in people with IBS. The low-FODMAP diet can help identify which foods trigger your IBS symptoms. Avoiding these foods may help you manage your condition.
How to Follow a LOW FODMAP Diet
A low FODMAP diet should only be used by people who have been diagnosed with IBS by a doctor. It is an elimination diet used to help find which foods cause IBS symptoms.
Here is how the diet works:
- You will stop eating all foods that are high in FODMAPs. (Below see the list of some high-FODMAP foods.) Over time, you may notice that your symptoms improve.
- After about 6 weeks, your provider will have you add back foods, one at a time, to see what foods trigger symptoms. Not all foods will bother every person.
- After you find the foods that cause symptoms, you can limit or stop eating those foods, and resume eating the foods that don't bother you. (For a list of some low-FODMAP foods, see below.)
It's important to work with your health care provider or a dietitian if you want to try the FODMAP diet.
- It's not easy to tell what foods are high in FODMAPs, so you'll need help to know what foods to avoid and what to eat.
- Because the diet is restrictive, your provider will ensure that you continue to get the proper nutrients.
The low FODMAP diet may not help everyone with IBS. You may need other types of treatment, such as lifestyle changes and medicines to better manage your IBS.
High FODMAP Foods
This is a partial list of the foods you should avoid while following the low FODMAP diet. This is not a complete list.
- Garlic, garlic salt, garlic powder, pickled garlic - avoid entirely if possible
- Onions, onion powder, pickled onions - avoid entirely if possible
- Brussels sprouts
- Green and yellow beans
- Sugar snap peas
- Summer squash
Fruit can be high in fructose, so it's best to avoid eating a lot of any fruit.
- Apples, applesauce, apple juice
- Canned fruit in fruit juice
- Dried fruit (raisins, currants, dates, figs, prunes)
- Fruit juice
BEANS AND LEGUMES
- Black-eyed peas
- Chick peas
- Lima beans
- Kidney beans, cannellini beans
- Pinto beans
- Soy beans
- Split peas
MEAT, POULTRY, AND SEAFOOD
Many marinated or processed meats have high FODMAP ingredients such as garlic and onion. So you should avoid:
- Marinated meat, poultry, or seafood
- Sausages and salami
- Some processed meats
DAIRY AND DAIRY ALTERNATIVES
- Cow, goat, and sheep milk and milk products
- Coconut milk
- Ice cream
- Soft unripened cheeses and fresh cheeses –brie, cottage cheese, cream cheese, ricotta, sour cream
- Soy milk
Check food labels and avoid breads, cereals, pastas, cookies, snack bars, and pastries made with:
- High fructose corn syrup
Many sugar-free gums and candies contain these sugar substitutes:
- Chamomile, chia, dandelion, fennel, and oolong tea
- Rosé wine
- Soft drinks made with high-fructose corn syrup
Low FODMAP Foods
You can eat the following foods while on a low-FODMAP diet. This is not a complete list. Be sure to work with your health care provider or a dietician to make sure you get a balanced diet while on the low FODMAP diet.
- Bell peppers
- Bok choy
- Green beans
- Winter squash
- Passion fruit
- Pineapple (limit)
MEAT, POULTRY, AND SEAFOOD
- Plain cooked meat: beef, chicken, lamb, pork, turkey
- Canned fish (check ingredients)
- Fresh fish and seafood
- Frozen fish and seafood (as long as nothing else is added)
DAIRY, DAIRY ALTERNATIVES, AND EGGS
- Almond milk
- Aged hard cheeses
- Cashew milk
- Lactose-free milk
- Lactose-free yoghurt
- Rice milk
NUTS AND SEEDS
- Almond butter
- Macadamia nuts
BREADS, CEREALS, AND PASTA
- Bread, pasta, cereal, pastries, and flours made from corn, potato, rice, oats, quinoa, or spelt
SWEETENERS AND SWEETS
- Dark chocolate
- Maple syrup
- Table sugar (sucrose)
- Rice malt syrup
- Diet soda
- Teas (other than chia, chamomile, dandelion, fennel, and oolong)
When to Call the Doctor
Call your provider if:
- You develop a fever
- You have gastrointestinal bleeding
- You have bad pain that does not go away
- You lose over 5 to 10 pounds (2 to 4.5 kilograms) when you are not trying to lose weight
Irritable bowel syndrome - low FODMAP diet
American College of Gastroenterology. Low-FODMAP diet. gi.org/topics/low-fodmap-diet/. Updated March 2021. Accessed April 28, 2021.
Barrett JS. How to institute the low-FODMAP diet. J Gastroenterol Hepatol. 2017 Mar;32 Suppl 1:8-10. doi: 10.1111/jgh.13686. PMID: 28244669 pubmed.ncbi.nlm.nih.gov/28244669/.
Dugum M, Barco K, Garg S. Managing irritable bowel syndrome: The low-FODMAP diet. Cleve Clin J Med. 2016 Sep;83(9):655-62. doi: 10.3949/ccjm.83a.14159. PMID: 27618353 pubmed.ncbi.nlm.nih.gov/27618353/.
Ford AC, Talley NJ. Irritable bowel syndrome. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 122.
Monash University. High and low FODMAP foods. www.monashfodmap.com/about-fodmap-and-ibs/high-and-low-fodmap-foods/. Accessed April 28, 2021.
Review Date 5/18/2021
Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.