Irritable Bowel Syndrome.

What is it? How to treat it?

We all have gastrointestinal disturbances, some of them can be mild, and other ones may feel terrible to the point that your quality of life becomes affected. Characterized by abdominal pain and a noticeable modification in bowel habits, irritable bowel syndrome (IBD) is the most common gastrointestinal tract disorder. Irritable bowel syndrome’s prevalence is estimated to be around 12-22%. Patients suffering from IBS are not only affected by gastrointestinal symptoms. Psychological disorders like anxiety and depression commonly follow this disease.

The main disturbances associated with IBS are abdominal pain, bloating, and constipation. Regularly IBS is commonly reported in women and often diagnosed in patients less than 50 years of age.

But what is exactly what happens? The truth is that this syndrome is not fully understood, especially considering that the symptoms and triggers vary in great amounts between patients. In summary, it is believed that the combination of low-grade inflammation, visceral hypersensitivity, motility changes, the microbiome, in addition to food components, are in the midst of the root cause of this illness. Furthermore, the chronic inflammation that accompanies IBS can result in the opening or rupture of tight junctions between the enterocytes, promoting the translocation of proteins or pathogens across the GI lumen.

Strictly talking about food-induced disturbances, a specific type of carbohydrates, labeled fermentable carbohydrates, is identified as IBS’s main trigger. These fermentable carbohydrates are commonly found in foods like dairy products, wheat, and fructose, beans cabbage. Furthermore, the treatment avoids these foods and limits others, like coffee, fatty foods, and alcohol. This type of diet is called FODMAP, fermentable oligo-, di-, and monosaccharides, and polyols.

The implementation of diet consists of an elimination period (4-8 weeks) of food triggers, always supervised and recommended by an experienced healthcare giver. Secondly, the reintroduction phase consists of evaluating signs and symptoms observed during the elimination phase and the consideration of introducing different foods, one at time. Lastly, the maintenance phase depends mostly on what foods were tolerated and which foods should be avoided.

Patients suffering from IBS that consume FODMAP containing food may go through the following process:

1.- In the small bowel, the consumed short-chain carbohydrates, which are osmotically active, increase the water content, therefore exacerbating intestinal transit.

2.- In the colon, these carbohydrates are rapidly fermented, and this process amplifies the gas production, causing distention.

Fermentable	Short-chain carbohydrates
Oligosaccharides	Wheat, onion, garlic, pulses, and legumes.
Disaccharides	Lactose, dairy products
Monosaccharides	Fig, honey, fructose.
And	And
Polyols	Stoned fruit, cauliflower, and xylitol are commonly found in sugar-free gum.

Accordingly, the benefits of a low FODMAP diet are reported in numerous research studies. Patients have reported a 68% improvement in gastrointestinal symptoms like abdominal pain and overall improvements in their quality of life. This treatment’s mechanism relies on reducing pro-inflammatory markers such as (ILs) IL-6 and IL-8. Subsequently, it should be mentioned that the FODMAP diet is considered a restrictive diet, and part of those restrictions include oligosaccharides, which could affect the microbiota profile. Hence the lower number of bifidobacteria and Faecalibacterium prausnitzii, in addition to the dairy exclusion, associated with low calcium intake.

So, what can I eat if I am following a low FODMAP diet?

LOW FODMAP
Dairy	Butter Cheeses: cottage, feta, mozzarella, swiss Lactose-free milk Tofu/Tempeh Eggs
Nuts and Seeds	Brazil nuts Chia seeds Flax seeds Macadamias Peanuts Pecan halves Pumpkin seeds Walnuts
Fats and Oils	Almond oil Avocado oil Butter/ghee Coconut milk Olive Safflower Sesame oil Walnut oil
Vegetables	Carrots Chives Eggplant Green beans Kale Potato Zucchini
Fruits	Blueberries Cantaloupe Grapes Lemon Oranges Pineapple Strawberry
Sweetener	Glucose Maple syrup Sucrose
Animal protein does not contain carbohydrates. Legumes have moderate to high FODMAP.

In conclusion, a low FODMAP diet is the most common treatment to control IBS’s adverse symptoms. Nevertheless, since it is a restrictive, challenge-based diet, the importance of following the advice of an experienced physician is necessary. It is essential to keep in mind that a balanced, varied, and sufficient diet plays a key role in health maintenance.

Weaver, Kristen Ronn et al. “Irritable Bowel Syndrome.” The American journal of nursing vol. 117,6 (2017): 48-55. doi:10.1097/01.NAJ.0000520253.57459.01

 

Drisko, Jeanne, et al. “Treating irritable bowel syndrome with a food elimination diet followed by food challenge and probiotics.” Journal of the American College of Nutrition 25.6 (2006): 514-522.

Rej, A., et al. “The role of diet in irritable bowel syndrome: implications for dietary advice.” Journal of internal medicine 286.5 (2019): 490-502.

Hayes P, Corish C, O’Mahony E, Quigley EM. A dietary survey of patients with irritable bowel syndrome. J Hum Nutr Diet 2014; 27(Suppl 2): 36– 47.

Tuck, Caroline J., et al. “Food intolerances.” Nutrients 11.7 (2019): 1684.

Institute of Functional Medicine.” Overview of the Low-FODMAP Diet.” IFM (2020)