Got IBS? Try the Low FODMAP Diet

FODMAP acronym graphic

This is a guest blog post by Kate Scarlata, RD.

Finally, a diet that has the potential to manage symptoms in 3 out of 4 people with irritable bowel syndrome (IBS) is going global! Researchers from Australia’s Monash University have been implementing the low FODMAP diet for some time, noting its ability to make people with digestive woes gain back their life.  But…now the world is taking notice and those with IBS want to learn more!

Say what? What’s a FODMAP anyway?

Although the name may sound like the latest GPS technology, FODMAP is actually an acronym describing a group of small carbohydrates known to contribute to the classic IBS symptoms:  gas, bloating, abdominal pain, diarrhea and/or constipation. The FODMAP family includes: lactose (found in milk and milk products), fructose (only when found in excess of glucose in certain fruits, vegetables, honey and agave syrup), fructans (found in chicory root extract, onion, garlic, wheat) and galacto-oligosaccharides also known as GOS (sources include legumes such as kidney beans) and polyols (sugar alcohols naturally found in some fruits, vegetables and added as artificial sweeteners.)

How do FODMAPs impact IBS symptoms?

When FODMAPs are malabsorbed they draw water into the intestine, which can contribute to osmotic diarrhea.   When these sugars are not digested properly, they travel through the intestine and become food for intestinal bacteria.  (It’s okay; we all have bacteria in our intestines!) When the bacteria consume the FODMAPs they produce gas and the IBS intestine is particularly sensitive to that gas. Ouch!

So who malabsorbs FODMAPs?

For starters, no one digests fructans and GOS because humans lack the enzymes to break them into absorbable sugars.  Lactose is malabsorbed in those who lack the intestinal enzyme lactase, which breaks lactose into digestible components. Fructose is malabsorbed in about 30-40% of individuals. The absorption of fructose requires special glucose transporters; foods are best absorbed when equal amounts of fructose and glucose are present in the food.  Polyols are large sugars that are not absorbed efficiently in most people.

Individuals that have IBS seem to be more vulnerable to the aftermath of poorly digested FODMAPs perhaps because the amount of gas produced in their large intestine is greater or the gut is hypersensitive to the osmotic effects of FODMAPs.

To begin to navigate the world of FODMAPs, start with the FODMAP checklist found here.

This checklist separates the cautionary foods, those notoriously high in FODMAPs from the FODMAP friendly foods which containing negligible amounts.

Although shopping for a low FODMAP diet may seem daunting at first, this easy to read low FODMAP grocery list will get you started!

If you have been diagnosed with IBS and continue to live with digestive woes, perhaps the low FODMAP diet is worth a try! The low FODMAP diet is a specialized diet that is best implemented by a registered dietitian knowledgeable in the diet specifics to provide the most accurate information about the diet and ensure that your diet is nutritionally balanced.

Kate Scarlata, RDKate Scarlata is a Boston-based registered dietitian and the author of The Complete Idiot’s Guide to Eating Well with IBS (Alpha 2010). She is currently working on an international food analysis study with the  FODMAP research team in Melbourne, Australia.



Barrett, JS, Irving PM, Shepherd SJ, Muir JG, Gibson PR Comparison of the prevalence of fructose and lactose malabsorption across chronic intestinal disorders. Aliment Pharmacol Ther 2009 30, 165-174

Gibson PR, Shepherd SJ. Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach. J Gastroenterol Hepatol. 2010;25(2):252-258.

The Low FODMAP diet booklet 3rd edition Monash University 2012

Muir JG, Rose R, Rosella O, Liels K, Barrett JS, Shepherd S, Gibson PR. Measurement of short-chain carbohydrates in common Australian vegetables and fruits by high-performance liquid chromatography (HPLC). J Agric Food Chem. 2009;57(2):554-565.

Staudacher HM, Whelan K, Irving PM, Lomer MC Comparison of symptom response following advice for a diet low in fermentable carbohydrates (FODMAPs) versus standard dietary advice in patients with irritable bowel syndrome. J Hum Nutr Diet 2011 24(25);487-495.


  • Millie Barnes

    It is not enough to take the offending foods out; the protocol for healthy a leaky gut is crucial because you have to repair the gut as well as allow the immune system to heal. This takes high quality proteins, traditional meat stocks, avoidance of all grains (not just gluten containing ones), avoiding all soy and plenty of organic saturated fats for the depth of nutrients they contain.

  • Jessica Stepper

    So basically, just don’t eat anything??

    • Karen Z

      No, you don’t have to avoid everything…just what triggers symptoms. It take does a lot of effort to figure out the low-FODMAP diet, but once you are following it accurately you should begin to notice positive changes in your GI health. As Kate Scarlata, RD notes, working with a RD who has the specific training to guide you is the best way to start. It took me many months of trial and error with inaccurate information before I located Kate. She was an invaluable resource.

  • Kate Scarlata, RD

    The low FODMAP diet may seem quite restrictive at first but since it makes the gut calm for 75% of those with IBS, I find my clients are willing to make the change. Quality meats, eggs, tofu, whole grains such as quinoa, oats, brown rice, and allowable fruits such as strawberries, oranges, bananas, kiwifruit, blueberries and grapes–and many vegetables such as spinach, potatoes, zucchini, carrots, parsnips, turnip are allowed on the initial phase of the diet. Working with a knowledgable dietitian is key to help create menus with variety and good taste. This diet is designed not to be a life long diet but one in which the individual with IBS can identify the foods that are the real culprit for their symptoms.

    • DraMaru

      Hi Karla. I’m an MD that counsels many diabetics and insulin resistant patients. What do you advise to people with both illness, diabetes&IBS? They cannot surely eat many of the foods since they have glycemic issues with the listed groceries.

  • Brian

    My IBS went away after I rid my system all all dairy products. Knowledge gained by reading ‘The Irritable Bowel Syndrome Solution’ by Dr. Wangen. I love this web site.

  • james

    Just eating easily digestible raw fruits, greens, and vegetables seem to work well for many people to curb their colitis and IBS symptoms. One of the many benefits of becoming a raw foodist seems to be that many people’s colitis and IBS goes away, or so I see that a lot on raw food forums. Green smoothies (greens mixed with fruit in a blender or juicer) seem to be the main thing that helps a lot. People just don’t eat enough greens.

  • Catherina Lucy

    IBS, according to my GI specialist, is a disorder of motility arising from misfires in the enteric nervous system.