By Dr Jane Varney
We’ve recently published a review article in the journal, Gastroenterology.
In the article, we summarise evidence supporting the most common dietary approaches to IBS treatment, some of which are better supported by research evidence than others! We review ‘whole-food’ approaches that require individuals to undergo testing to detect intolerances to specific whole-foods, for example strict elimination-rechallenge diets and diets that identify food sensitivities based on the presence of immune markers (IgG 4).
We also look at the more contemporary, ‘food components’ approach. This approach acknowledges that food is a complex mixture of different food components, including carbohydrates (for example FODMAPs), proteins (for example gluten), fats and naturally occurring food chemicals (for example salicylates, amines and glutamates), all of which have different effects on gut symptoms.
An advantage of the ‘food components’ approach is that once sufficient evidence from clinical trials can implicate a specific food component as a trigger of IBS symptoms, the research focus can shift from testing participants, to testing foods for their content of the specific food component.
Diets can then be designed based on their exclusion of the specific food component. This is advantageous in a global and evolving food chain that sees new food products arrive on supermarket shelves every week. Time consuming, labour and resource intensive methods of testing the tolerability of whole food in IBS sufferers (such as elimination-rechallenge diets) cannot keep pace with this changing market. By contrast, nutrient analysis of foods can occur relatively quickly and cheaply.