• Yasmin Norazharuddin

IBS and food intolerances

The majority of people with IBS have a type of food intolerance. Food intolerance is a condition where the gut is sensitive towards a certain food or has trouble digesting it properly. Symptoms are mostly in the form of gastrointestinal issues like diarrhea, passing gas, abdominal cramps, vomiting, and nausea. Sounds familiar?

Food intolerance is totally different from food allergy mainly because food allergy is an overreaction of immune response in the body while food intolerance does not interfere with the immune response.

Most common food intolerances:

Milk (lactose and casein)

The lactose and casein in milk are usually the culprits. Some people cannot produce lactase which is the enzyme that breaks down lactose thus making it difficult to digest. GPs and dietitians may advise lactase supplements so that patients can enjoy dairy with ease, depending on the level of intolerance. Milk and dairy products have essential nutrients that the body needs like calcium, phosphorus and it’s also a good source of protein.

Wheat and gluten for IBS

What about coeliac disease? Isn’t that an auto-immune disease? Yes, and there is also such thing as non-coeliac gluten sensitivity (NCGS) where the symptoms are not as harmful compared to coeliac disease. People with NCGS experience gastrointestinal symptoms like bloating, wind, vomiting, and abdominal cramps, but symptoms similar to coeliac disease can also be seen like fatigue, headache, and ‘foggy brain’.

Wheat intolerance is usually due to the fructan that is available in wheat. Fructan also falls under FODMAP foods which are common food triggers for IBS.

IBS with beans and legumes

Some people are less tolerant towards these tooting vegetables due to the indigestible fiber which ferments and releases gas as a by-product. People with weaker gut and may lack a specific enzyme to help break down the fibre.

If you love beans, pharmacies usually carry supplements that can reduce gas production in the gut by helping the digestion of complex carbohydrates that can be found in vegetables, fruits, and even beans and legumes! One of the most well-known examples is Beano. Refer to your GP about this or other recommended brands.


FODMAPS in particular are foods that are people with IBS are sensitive to. These include a list of food from garlic, onions, peaches, and wheat (fructans). BUT, not every IBS sufferer is intolerant towards every food on the FODMAP list. People with IBS tend to avoid FODMAP foods in total and that leads to undernutrition and malnutrition.

Ensure you are diagnosed properly and discuss with your GP or dietitian the relevance of you eliminating FODMAP foods.

IBS symptoms usually aggravate when you eat food that you are not tolerant of. But, remember that you can still enjoy them from time to time during remission. Here are some tips:

  1. Have a small amount and try to keep the serving as once a day. Even though you are not eating a lot in one sitting, you are still loading your gut over time and will eventually trigger the gas or abdominal pain towards the end of the day.

  2. For legumes, beans, and vegetable intolerance, try cooking them thoroughly to help break the fiber further and reduce the digesting burden.

  3. Did you know some cheeses are lower in lactose than others? Look for hard and semi-hard cheeses like aged cheddar, asiago, gruyere, and emmental. Butter is also low in lactose!

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