Increasing fibre intake is one of the main recommendations for Irritable Bowel Syndrome (IBS), but whether or not it’s helpful depends on the type of IBS you have.
There are 3 types of IBS:
- - Constipation dominant IBS
- - Diarrhoea dominant IBS
- - Alternating constipation & diarrhoea IBS
A low fibre diet does not cause IBS, however, it can exacerbate symptoms of IBS if you have constipation predominant IBS. Soluble fibre (eg fibre in oats) is usually better tolerated than insoluble fibre (eg nuts & legumes) by people with IBS. You should increase your intake of fibre slowly and make sure you drink plenty of water, because increasing fibre intake without adequate hydration can make constipation worse.
One of the most common causes of IBS symptoms is intolerance to one or more of the FODMAPs. If you increase your fibre intake and you continue to experience symptoms, then you might consider FODMAPs as a cause of your IBS. The Low FODMAP diet is a type of elimination diet that’s best done with the guidance & supervision of an Accredited Practising Dietitian. The Low FODMAP diet is quite strict and you want to make sure you get it right the first time round!
Finally, the symptoms of IBS are often similar to gluten intolerance, diverticulitis and other gastro conditions, so it is important to medically rule out any other causes of your symptoms before ‘treating’ IBS.