IBS and the Important Role of the Low FODMAP Diet

–Vanessa Cobarrubia, RDN 

Have you been diagnosed with IBS (Irritable Bowel Syndrome)? Are you familiar with the low FODAP diet? Researchers at Monash University in Melbourne, Australia discovered the low FODMAP diet approximately 10 years ago which is proven to be the most effective approach to managing IBS symptoms. Approximately 75% of IBS sufferers experience symptom relief when adapting a low FODMAP diet.

FODMAPs are a group of carbohydrates, sugars and fibers found in many foods that can cause digestive issues such as bloating, excessive gas, abdominal pain, constipation, and diarrhea after consumption for those suffering with IBS. These carbohydrates are often poorly absorbed, quickly fermented by your gut bacteria, and often contribute to intestinal fluid shifts- all contributing to IBS symptoms. When gut bacteria breaks down FODMAPs, the byproduct is gas (hydrogen, carbon dioxide and methane) which contributes to increased intestinal pressure resulting in abdominal pain, bloating, and excessive gas. High FODMAP foods can pull fluid into your large intestines resulting in fluid shifts which can lead to diarrhea and/or constipation. Many FODMAPS are malabsorbed in the small intestine which also play a role in IBS symptoms.  Symptoms can occur soon after a meal, or many hours later making it challenging for people to identify their food intolerance.  By consuming a diet low in FODMAPs, most of those suffering with IBS see improvements in abdominal pain, bloating, gas, diarrhea, and constipation.

FODMAP stands for the following:

F = Fermentable – Quickly broken down by gut bacteria in the large or small intestine producing excessive gas.

O = Oligosaccharides – Found in asparagus, legumes, wheat, onions, garlic, cashews, pistachios, chicory root, and herbal teas.

D = Disaccharides (Lactose) -Also called milk sugar which is found in cow’s milk and many dairy products.

M = Monosaccharides (Fructose) – Found in some fruits, vegetables and sweeteners such as honey and agave.

A = And

P = Polyols (Sugar Alcohols) – Found in may stone fruits, vegetables, low carb protein bars,  and sugar free, no sugar added products.

It is important to remember that the low FODMAP is a three part diet journey:

1. The first part of the low FODMAP diet is the elimination stage which can last 3-6 weeks.
2. The next part is the re-challenge or reintroduction stage where one adds back FODMAP groups in a slow, methodical process with the goal of determining which FODMAP groups they are intolerant to and learns safe thresholds of these foods.
3. The last part is learning how to live on a adapted low FODMAP diet forever to keep IBS symptoms in control.

It is not recommended to remain on the elimination diet forever and in some situations this may not be the best first approach. It is highly recommended to work with a registered dietitian who specializes in the low FODMAP diet. The end goal is to have the most varied diet one can tolerate. Many high FODMAP foods are rich in prebiotics which play an important role in gut health.

About the Author:

Vanessa Cobarrubia, RDN is a registered dietitian nutritionist at Summit Medical Group Oregon and has passion for helping others improve their digestive health. She has 18 years of experience working closely with bariatric surgeons, gastroenterologists, and physicians. Late last year the Monash University launched their online training course The Low FODMAP Diet for Irritable Bowel Syndrome for health professionals and Vanessa completed this training. Vanessa battles with IBS herself and follows an adapted modified low FODMAP diet.  She has been educating patients on the low FODMAP diet in her outpatient practice for the past two and a half years.

Specialties include:

• Irritable bowel syndrome (IBS)
• Completed the Monash University RDN training for the Low FODMAP Diet for Irritable Bowel Syndrome
• Small intestinal bacterial overgrowth (SIBO)
• Bariatric surgery
• Inflammatory bowel disease (Crohn’s disease, Ulcerative colitis)
• Lactose intolerance
• Enteral nutrition (tube feedings)

Print