Irritable bowel syndrome: can nutrient manipulation help?

To describe the evidences for the usefulness of dietary manipulations (including the use of probiotics and prebiotics) in the management of irritable bowel syndrome (IBS).

Exclusion diets do not have a role in the management of these patients except in the case of malabsorbed sugars (lactose, fructose). However, recent work suggests that excluding these sugars is more effective in non-IBS than in IBS patients. Also, the first small open series on the use of very low (20 g/day) carbohydrate diet (VLCD) in IBS has been published with promising results. However, safety concerns do not allow us to recommend them. In the period of review, further evidence has been provided on the role of psyllium in IBS. Also, the available evidence on the use of probiotics in IBS has been meta-analyzed.

IBS patients should eat a balanced diet without restrictions, and (except for malabsorbed sugars) exclusion diets are not useful in most of them. The role of VLCD remains to be established. The concept that increasing fiber intake is useful for IBS may not be true for all patients, and hydrophilic colloids (e.g. psyllium) are preferred. There is growing evidence for the effectiveness of probiotics in IBS.