Low FODMAP Diet for IBS

Female hands are covering belly becuase of strong stomach pain

Not many of us like to talk about our bowel habits. But did you know that 1 in 5 Americans has irritable bowel syndrome? I have been seeing this more and more in my private practice. IBS is a disorder which can include abdominal pain, bloating, gas, diarrhea, constipation, or alternating episodes of both and can be an extremely debilitating for some people. For many years, it was thought of a condition that “stressed out” people got. But we now know that it is a real medical condition with a wide range of GI symptoms. The exact causes are unknown but may include family history of IBS, a bout of food poisoning and small intestinal bacterial overgrowth. There is no one single proven treatment for IBS. But the good news is that diet has been shown to play a major role in alleviating symptoms in ~70% of people. Read on to learn more about the Low FODMAP diet for IBS. April is National IBS Awareness Month so I thought this was good timing for this post.


How I got involved with diet for IBS
I took a workshop on IBS and the Low FODMAP diet taught by Patsy Catsos, RD and Kate Scarlata, RD 3 years ago. It was one of the best workshops I’ve ever attended!  I’ve since taken several more seminars on this topic as the field is always changing.  I just attended a lecture/lunch on Low FODMAP diets yesterday taught by Kate yesterday sponsored by Nestle Health Science (who just launched LowFODMAPcentral.com)  I now see quite a few clients each week with IBS and most have had an improvement in symptoms with the Low FODMAP diet.


My first patient with IBS
I clearly remember my first patient with IBS 3 years ago as I was fresh out of my IBS & Low FODMAP diet workshop. I was questskeptical but hopeful that the diet would help her. She was a 28 year old lean, athletic female with IBS and suffered from bloating, gas and constipation. In attempts to alleviate the constipation, she followed a high fiber diet with a lot of vegetables, apples, bran cereal and Quest bars. She was always trying to lose a few pounds to better fit into her pants (due to bloated stomach) – however she was quite thin and didn’t need to lose weight. I told her we were going to do an experiment with the Low FODMAP Elimination diet. She cut out all the potentially problematic foods and felt 90% better within a week. After the 4 weeks, we began the “challenge phase” and were able to pinpoint which group of carbohydrates triggered her symptoms. She is now symptom free for the most part as long as she avoids/limits her trigger groups of fermentable carbs. 


So … what is the Low FODMAP diet?
This diet was first developed by Dr. Sue Shepard in 1999. Much of the research comes out of Monash University in Melbourne, Australia. The Low FODMAP diet has been published in international medical journals and is now accepted and recommended as one of the most effective dietary therapies for IBS.  (pic credit fodmap-banner)

FODMAP is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols. These are specific types of short-chain carbohydrates that can be poorly absorbed in the small intestines leading to the symptoms mentioned previously. Here are some examples of FODMAPS (this is only a partial list):
Oligosaccharides found in fructans and GOS: wheat, rye, onions, garlic, artichokes, inulin, red kidney beans, cashews
Disaccharides found in lactose: milk, yogurt, ice cream, pudding
Monosaccharides found in excess fructose: high fructose corn syrup, honey, agave, mango, watermelon
Polyols found in sorbitol and mannitol: sugar free products, blackberries, apples, pears, peaches, cauliflower, mushrooms, snow peas

Note: this doesn’t mean you need to stay away from all these foods if you have IBS. You’ll do a little experimentation to see which of them worsen  your symptoms by trying the Low FODMAP elimination diet for 2-6 weeks. You will then systematically add in one group of fermentable carbs at a time and pay close attention to symptoms. By the end of the reintroduction phase, you should have a pretty good idea of which foods worsen symptoms and which are ok. 


Tips when trying the Low FODMAP diet
1. Work with your doctor to rule out any other medical conditions. IBS is a diagnosis of exclusion. Also, make sure you’ve been tested for celiac disease before starting this diet as this does eliminate many grains with gluten as they also contain fructans (and you need to be consuming gluten in order to be tested for celiac disease)

2. The Low FODMAP diet consists of 2 parts: the elimination phase and the reintroduction phase.
3. Work with a nutritionist who specializes in Low FODMAP diets. The elimination diet and reintroduction of foods can be quite confusing. You want to do it correctly!
4. The stricter elimination Low FODMAP diet is not a long term diet. It is short term “experiment” that is generally followed for 2-6 weeks. Many of the foods excluded in this diet contain healthy prebiotics that are needed to maintain healthy levels of “good bacteria”
5. Do your best to choose healthy foods and eat a balanced diet while on the Low FODMAP diet
6. Take detailed notes when introducing new foods in the “challenge” phase. This is when you and your nutritionist put your detective hat on!


More research is neededdoctor and patient2
Unfortunately, research in the area of IBS is seriously lacking. This is shocking considering 20% of the population has IBS. As I stated previously, medications aren’t always effective in treating symptoms of IBS. Find a good team – gastroenterologist and registered dietitian to work with you. Consider other areas like stress management, mediation and exercise. While stress does not cause IBS, it certainly can aggravate it.  Keeping in mind that our gastrointestinal tract has more nerve receptors than our spinal cord(pic credit) 

Work with me
If you need guidance on the Low FODMAP diet, contact me to learn how I can help you at martha@marthamckittricknutrition.com or 212 – 879-5167



I can’t say enough good things about Kate and Patsy so be sure to check out their sites!
Kate Scarlata, RD    
Patsy Catsos, RD –  IBS Free  
Low FODMAP diet blog from Monash University   http://fodmapmonash.blogspot.com.au/
Low FODMAP diet app
LowFODMAPcentral.com     This site was just launched by Nestle and has great references for patients and health professionals
Numerous journal articles on Low FODMAP diets and IBS (taken from Dr. Sue Shepard’s website)  



I especially love problem-solving, whether it’s helping women defeat issues plaguing them for years, helping a busy executive find practical ways to get heart healthy, or providing tips to help you reverse diabetes. That’s why I’m on a constant quest to expand my knowledge by staying on top of the latest research.

  • Martha's Nutrition Page

    Looking for up to date information on nutrition?  Follow my nutrition page!

  • PCOS Nutrition

    Interested in the latest PCOS nutrition news?  Follow my PCOS page!

  • Twitter

  • Instagram

  • Pinterest

Leave a Comment


20 Ways To Eat Out 550 Calories or Less!

No time to cook? We’ve got you covered. Here are 20 healthy meals from a variety of cuisines that won’t pack on the pounds. Most of them also have less than 30 grams of carbs.

Subscribe to my newsletter and get this free download.

Something went wrong. Please check your entries and try again.