Irritable Bowel Syndrome (IBS)

Updated: Jan 3, 2021

According to National Institute of Health, IBS is a group of symptoms that occur together, including repeated pain in abdomen and changes in bowel movements, which may be diarrhea, constipation, or both, these symptoms occur without any visible signs of damage or disease in the digestive tract. IBS is also known as spastic colon, irritable colon, mucous colitis, and spastic colitis. IBS symptoms may not be persistent and can go away after an episode but can resurface due to a trigger. Causes of IBS are still unclear but following factors seem to play some role:

Probable causes:

  1. Stress: the digestive system is majorly controlled by our nervous system thus, excessive stress can make the digestive system overactive. In case of IBS, the colon may become extra sensitive to any digestive disruption. Stress also negatively affects the immune system, worsening IBS.

  2. Nervous system abnormalities: Poor coordination between brain and intestines via an abnormal nervous system can result in greater sensitivity towards any changes that normally occur in the digestive process, resulting in pain, diarrhea or constipation.

  3. Severe infection: IBS can develop after a severe gastroenteritis infection.

  4. Changes in gut microbiome: Studies have found that the bacteria, fungi and viruses that normally live in a healthy individual are different than the ones found in a person suffering from IBS.


  1. Abdominal pain

  2. Cramping

  3. Bloating and gas

  4. Diarrhea

  5. Constipation

  6. Changes in appearance and frequency of bowel movement

Most common triggers:

  1. Food: exact relationship between food and IBS is not clear but foods like dairy, wheat, citrus fruits, cabbage, caffeinated beverages, carbonated drinks and artificial sweeteners.

  2. Stress: excessive stress can worsen IBS or increase the frequency of symptoms.

Diet recommendations:

Although there is no cure for this disorder, diet and lifestyle modifications can help manage the symptoms. Simple home remedies can greatly help such as:

  1. Get plenty of exercise.

  2. Add probiotics in your diet.

  3. Avoid stress and make time to de-stress.

  4. Avoid or minimize consumption of spicy and fried foods.

  5. Maintain a food journal to identify trigger foods.

  6. Eat mostly home cooked food with fresh ingredients.

  7. Minimize consumption of coffee, tea, alcohol and carbonated drinks.

  8. Practice eating slowly and mindfully.

Adjusting fiber intake

When talking specifically about diet, fiber rich foods are placed on a continuum. For some IBS sufferers who experience diarrhea often, having a fair amount of fiber rich diet containing water insoluble fiber may help but for those who regularly experience constipation, bloating and gas, eating more water soluble fiber may be beneficial. Examples of foods rich in water insoluble fiber are beans, broccoli, cabbage, whole grains and nuts while best sources of water soluble fiber are berries, oatmeal, apples and carrots. Some patients are suggested to eat a low FODMAP diet, the acronym stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols, these are names of sugar molecules which make up the fiber in carb rich foods and are difficult for the intestines to digest. Click here for a comprehensive list on FODMAP foods

Elimination diets

People who are gluten and lactose intolerant have higher susceptibility to develop IBS symptoms and hence having gluten or lactose in their diet may incur serious digestive problems. Some people may experience IBS even after going on a low FODMAP diet, for them elimination diet is very helpful in which they completely remove a certain food or food group for atleast 12 weeks to observe any changes in their symptoms, this helps identify the culprits and makes it easier to manage the disorder.

IBS fasting

Fasting for short (16 hours) and long periods (24 hours) seems to be beneficial for some IBS patients probably because of two major factors. First, fasting helps with improving migrating motor complex (MMC) which are like cleansing waves occurring in upper gastrointestinal tract between meals and snacks. The MMC helps in regulating microbial growth in the small intestines and improves movement of contents through it. Secondly, fasting can promote autophagy (self degradation and rejuvenation of cells) of gut cells leading to reduced inflammation and promoting healthy gut microbiome. Recommendations for fasting can become counter-intuitive if a large portion of meal is consumed to break the fast; some individual may experience symptoms like acid reflux, stomach rumbling, cramps, and nausea as a result of being hungry for a long duration.

Superfoods for IBS:

It is difficult to recommend a definitive superfoods list for IBS as certain foods may be trigger for some while beneficial for others. Probiotic foods, low FODMAP foods and those rich in omega-3 fatty acids are the safest options as they are unlikely to worsen the symptoms.

  1. Probiotics: Yogurt, buttermilk and kefir.

  2. Omega-3 rich foods: Avacoado, chia seeds, flax seeds, and salmon.

  3. Ginger, olives, and coconut milk.

References and further reading:

Böhn, L., Störsrud, S., Liljebo, T., Collin, L., Lindfors, P., Törnblom, H. and Simrén, M., 2015. Diet Low in FODMAPs Reduces Symptoms of Irritable Bowel Syndrome as Well as Traditional Dietary Advice: A Randomized Controlled Trial. Gastroenterology, 149(6), pp.1399-1407.e2.

Chang, L., 2016. Irritable Bowel Syndrome (IBS) | NIDDK. [online] National Institute of Diabetes and Digestive and Kidney Diseases. Available at: <> [Accessed 15 November 2020].

Chey, W., Kurlander, J. and Eswaran, S., 2015. Irritable Bowel Syndrome. JAMA, 313(9), p.949.

Healthline. 2017. What Are The Most Common Symptoms Of An Irritable Bowel?. [online] Available at: <> [Accessed 17 November 2020].

Heizer, W., Southern, S. and McGovern, S., 2009. The Role of Diet in Symptoms of Irritable Bowel Syndrome in Adults: A Narrative Review. Journal of the American Dietetic Association, 109(7), pp.1204-1214.

Herndon, J., 2019. IBS: Symptoms, Causes, Diagnosis, Triggers, And Treatment. [online] Healthline. Available at: <> [Accessed 15 November 2020].

Lindberg, S., 2019. IBS Fasting: Benefits, Risks, Why It May Or May Not Work. [online] Healthline. Available at: <> [Accessed 15 November 2020].

Mayo Clinic. 2020. Irritable Bowel Syndrome - Symptoms And Causes. [online] Available at: <> [Accessed 15 November 2020].

Moayyedi, P., Ford, A., Talley, N., Cremonini, F., Foxx-Orenstein, A., Brandt, L. and Quigley, E., 2008. The efficacy of probiotics in the treatment of irritable bowel syndrome: a systematic review. Gut, 59(3), pp.325-332. 2017. Irritable Bowel Syndrome (IBS). [online] Available at: <> [Accessed 15 November 2020].

SHEPHERD, S., PARKER, F., MUIR, J. and GIBSON, P., 2008. Dietary Triggers of Abdominal Symptoms in Patients With Irritable Bowel Syndrome: Randomized Placebo-Controlled Evidence. Clinical Gastroenterology and Hepatology, 6(7), pp.765-771.

Vazquez–Roque, M., Camilleri, M., Smyrk, T., Murray, J., Marietta, E., O'Neill, J., Carlson, P., Lamsam, J., Janzow, D., Eckert, D., Burton, D. and Zinsmeister, A., 2020. A Controlled Trial Of Gluten-Free Diet In Patients With Irritable Bowel Syndrome-Diarrhea: Effects On Bowel Frequency And Intestinal Function.