Irritable bowel syndrome (IBS) is a digestive disorder that causes stomach pain, diarrhoea, and constipation. It’s possible that what a person eats has an impact on how their IBS manifests.
The symptoms of this illness, on the other hand, vary greatly from person to person. People’s reactions to various foods, as well as their other symptom causes, can differ.
As a result, no single IBS diet is guaranteed to work for everybody. People sometimes have to experiment with various solutions in order to discover what works best for them.
In this article, we examine some of the IBS diets that may be beneficial, as well as what they entail and how to select one. Other factors that may cause IBS flare-ups are also discussed, as well as when to seek medical help.
There is no one-size-fits-all diet that will benefit anyone with IBS. This is due to the fact that a person with IBS may have particular foods that cause their symptoms to worsen.
To try to classify trigger foods or food classes, the International Foundation for Gastrointestinal Disorders (IFFGD) recommends keeping a diary for 2–3 weeks.
The diary can be used to keep track of:
- the foods and beverages they consume on a daily basis
- the signs they have, including when they occur and how serious they are
- other factors, such as stress and hormonal fluctuations, can play a role
This diary can also be brought to medical appointments with a doctor or a dietitian.
If a diary does not help a person understand their IBS causes, an elimination diet can be beneficial.
An elimination diet is one in which a person eliminates certain foods or food groups from their diet for a period of time to see whether their symptoms improve.
Elimination diets should be tried for a total of 12 weeks, according to the IFFGD, by following these steps:
- Make a list of foods that you think may be contributing to your IBS symptoms. If you’re not sure which foods are causing your symptoms, keep a food diary or eliminate common causes like fibre or caffeine first.
- Select one food or food category from the list and exclude it from your diet for a period of 12 weeks.
- Reintroduce the food and remove a different one if the IBS symptoms do not improve.
Fiber may be an IBS cause, even in those who have IBS with constipation, according to the IFFGD, so it’s best to eliminate it from the diet first.
It’s critical to seek medical or dietitian advice before attempting this method. When you exclude foods from your diet, it can be difficult to get the nutrients you need. This can be avoided with the assistance of a medical professional.
Diet low in FODMAPs
“Fermentable oligosaccharides, disaccharides, monosaccharides, and polyols” is the acronym for “fermentable oligosaccharides, disaccharides, monosaccharides, and polyols.” These are short-chain carbohydrates that can be found in a variety of foods. Foods high in FODMAPs have been known to cause IBS symptoms in some individuals.
The Low FODMAP Diet was developed by Monash University in Melbourne, Australia, to help with this. For a fixed period of time, the diet entails consuming low FODMAP foods in the appropriate portion sizes.
According to a study from 2016, up to 86 percent of people with IBS found that eating a low FODMAP diet helped them feel better.
The table below lists some foods that are high in FODMAPs or low in FODMAPs. It is not, however, a comprehensive list of low FODMAP foods or portion sizes. The complete list can be found on the Monash University website. A mobile app has also been created by Monash University.
|Food group||High FODMAP||Low FODMAP|
|vegetables||garlic, onions, and other alliums|
beans, including black eyed beans and baked beans
|dairy and alternatives||cow’s milk|
soy milk made from whole soybeans
mature, hard cheeses
soy milk made from soy protein
|protein||some marinated or processed meats if they contain high FODMAP seasoning||plain meats|
|breads and cereals||anything containing wheat or rye flour, including breads, cookies, crackers, baked goods, pasta, and couscous||sourdough bread|
|sugary foods||high fructose corn syrup|
artificially sweeteners such as sorbitol, mannitol, and xylitol
|nuts and seeds||cashews|
To try the diet, follow these steps:
- Stop high FODMAP foods for 2–6 weeks, replacing them with low FODMAP foods. Since this can necessitate major dietary changes, consulting a dietitian can be beneficial.
- Begin gradually reintroducing one kind of FODMAP at a time after 6 weeks by consuming one particular food that contains it. Honey, for example, can be used to determine a person’s fructose tolerance.
- Eat a small, regulated portion of that food for three days, steadily growing it. Keep an eye out for signs during this period.
- If a person experiences symptoms after reaching a certain portion size, they should write it down to remember what they can handle and what they cannot.
- Over the next 8–12 weeks, repeat these steps for each form of FODMAP.
People can then balance low FODMAP foods with higher FODMAP foods that they may be able to tolerate after this time.
Diet rich in fibre
Increased fibre intake can help certain people with IBS symptoms including chronic constipation.
Soluble and insoluble fibres are the two types of fibre. Soluble fibre is found in foods like fruits, oats, and beans, and it dissolves in water. Whole grain foods contain insoluble fibre, which does not dissolve in water.
Soluble fibre is often recommended by doctors to people who suffer from IBS. However, in some patients, both types of fibre may help with different IBS symptoms.
Bloating and excessive gas output can be reduced with soluble fibre. However, some soluble fibre sources are also high in FODMAPs.
In general, it’s best to start with a small increase in fibre intake and work your way up. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) suggests that people add 2–3 grams of fibre a day to their diet before they find an amount that fits them.
If increasing fibre intake worsens symptoms, a person may gradually increase their intake. If that doesn’t work, they may want to try something else.
Aside from the foods an individual consumes, there are other factors that may lead to IBS symptoms. These include:
- too much or too little exercise
- eating too much or too quickly
- hormonal fluctuations, such as those that occur before menstruation
- certain medications
A symptom diary may be used to keep track of these factors as well. A combination of dietary and lifestyle improvements can be beneficial. People can, for example, try:
Digestion is aided by chewing food slowly and thoroughly. It can also make it difficult for a person to swallow air, which can make them feel bloated. Carbonated drinks should be avoided, particularly at mealtimes.
Moderate physical activity
Taking care of mental wellbeing
According to the National Institute of Diabetes and Digestive and Kidney Diseases, while IBS is a physical illness, people who have it are more likely to have endured traumatic events in their childhood.
A 2018 meta-analysis of over 648,000 participants found that early trauma and post-traumatic stress disorder raised the risk of IBS. Trauma may have long-term consequences on both mental and physical wellbeing.
Some people may find it beneficial to speak with a trauma-informed therapist about this. Even if it is not a direct IBS cause, reducing stress is usually beneficial for digestion.
When do you see a doctor or a dietitian?
Before making any significant dietary changes, a person should consult with a doctor or a dietitian. If a person notices any symptoms of malnutrition, they should see a doctor, such as:
- reduced appetite
- unintentional weight loss
- feeling weak or tired all the time
- getting ill often
- slow wound healing
- difficulty concentrating
- feeling cold
A dietitian can assist a person in experimenting with various IBS diets, creating meal plans, and, if necessary, recommending vitamin and mineral supplements.
People with IBS should try a variety of diets to help control their symptoms and improve their quality of life.
It’s important to keep in mind, however, that what works for one person may not work for another. A combination of dietary and lifestyle changes can be needed at times.
- 12 week elimination diet for IBS. (n.d.).
- Dietary fiber. (2014).
- Eating, diet, & nutrition for irritable bowel syndrome. (2017).
- Irritable bowel syndrome diets and how to choose one. https://www.medicalnewstoday.com/articles/ibs-diet
- El-Salhy, M., et al. (2017). Dietary fiber in irritable bowel syndrome (review).
- FODMAPs and irritable bowel syndrome. (n.d.).
- Gibson, P. R. (2017). History of the low FODMAP diet.
- IBS diet: What to do and what to avoid. (n.d.).
- Irritable bowel syndrome. (n.d.).
- Irritable bowel treatments aren’t one-size-fits-all. (2017).
- Malnutrition: Symptoms. (2020).
- Nanayakkara, W. S., et al. (2016). Efficacy of the low FODMAP diet for treating irritable bowel syndrome: The evidence to date.
- Ng, Q. X., et al. (2018). Systematic review with meta-analysis: The association between post-traumatic stress disorder and irritable bowel syndrome [Abstract].
- Starting the FODMAP diet. (n.d.).
- Symptoms and causes of irritable bowel syndrome. (2017).
- What causes IBS? (n.d.).