Dietary interventions and irritable bowel syndrome - what really works?

Gastrointestinal effects of diets low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols

PURPOSE OF REVIEW

Food ingestion is an exacerbator of gastrointestinal symptoms, regardless of origin. Sufferers mistakenly assume that they have suffered an allergic reaction to a given food. Although classical IgE-mediated allergic reactions are rarely culpable, evidence for a role for intolerance to certain carbohydrates in irritable bowel syndrome (IBS) and related conditions increases. This review assesses the status of a commonly implicated group of poorly absorbed carbohydrates (fermentable oligosaccharides, disaccharides, monosaccharides and polyols - FODMAPs) in gastrointestinal pathophysiology.

RECENT FINDINGS

Although evidence of efficacy for low FODMAP diets in IBS accumulates, the magnitude of this effect has declined in recent studies. Comparisons to other dietary approaches have revealed conflicting results; some suggest superiority, others find parity. Concerns had been raised regarding long-term nutritional, psychological and microbiological impacts of FODMAP restriction; providing that the diet is administered in the recommended manner, these do not appear to be clinically important. The mechanisms whereby FODMAPs cause gastrointestinal symptoms continue to be explored.

SUMMARY

FODMAPS induce gastrointestinal symptoms in susceptible individuals and their restriction provides clinical benefits. The magnitude of these benefits, the superiority of FODMAP restriction over other dietary approaches and the mechanisms of its effects continue to be defined.

Diet, fibers, and probiotics for irritable bowel syndrome

Many aspects make irritable bowel syndrome (IBS) challenging for both patients and physicians. The unclear pathogenesis with many pathways to be explored, bothering symptoms that affect the quality of life, and many subtypes of the condition are only a few reasons that make IBS difficult to control and obtain satisfactory results. Treatment options start with general advice for lifestyle, continue with non-pharmaceutical treatments, and finally touch classic treatments. In this review, pharmaceutical treatment options are not accounted for. Consensus groups and meta-analyses have concluded guidelines that overall are the same, with variations in the strength of recommendations and some cultural and geographical particularities. Dietary interventions, probiotics, and fibers can be seen as non-pharmaceutical treatments that coexist in various protocols because of the relevant evidence regarding their efficacy in treating IBS symptoms.