What is a Low FODMAP (Fermentable Oligo-, Di-, Mono-saccharides, and Polyols) diet?

From the Guidelines

The FODMAP diet is a highly effective, evidence-based dietary treatment for managing symptoms of irritable bowel syndrome (IBS), consisting of three phases: restriction, reintroduction, and personalization, as recommended by the most recent and highest quality study 1. The diet involves eliminating foods high in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs), which are types of carbohydrates that can be poorly absorbed in the small intestine. Some key points to consider when implementing the FODMAP diet include:

• The restriction phase should last no more than 4-6 weeks, as recommended by the AGA clinical practice update 1.
• The reintroduction phase is critical for identifying specific FODMAP triggers and should be done systematically, with guidance from a registered dietitian.
• The personalization phase involves creating a long-term diet that excludes only problematic FODMAPs, which can help improve overall diet quality and reduce symptoms. The FODMAP diet has been shown to be effective in reducing global symptoms, abdominal pain, and bloating in patients with IBS, with a recent network meta-analysis ranking it as superior to all control diets 1. It is essential to note that the FODMAP diet should be implemented with caution in individuals with moderate to severe symptoms of anxiety or depression, as it may have limited evidence for efficacy on psychological symptoms 1. Overall, the FODMAP diet is a valuable treatment option for managing IBS symptoms, and its implementation should be guided by the most recent and highest quality evidence, with consideration of individual patient needs and circumstances.

From the Research

Overview of FODMAP Diet

• The FODMAP diet is a dietary approach that restricts the intake of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) to manage symptoms of irritable bowel syndrome (IBS) 2, 3, 4, 5, 6.
• The diet is typically administered in three phases: restriction of all dietary FODMAPs, followed by rechallenge and then reintroduction of specific FODMAPs according to the tolerance of patients 2, 3.

Phases of FODMAP Diet

• Restriction phase: All high FODMAP foods are removed from the diet to assess symptom improvement 2, 3.
• Rechallenge phase: FODMAPs are reintroduced one at a time to identify which ones trigger symptoms 2, 3.
• Reintroduction phase: Patients are advised to follow a personalized diet that excludes their individual FODMAP triggers, allowing for a more diverse dietary intake 3.

Benefits of FODMAP Diet

• The low FODMAP diet has been shown to improve symptoms, stool output, quality of life, and overall well-being of patients with IBS 2, 4, 6.
• Up to 86% of patients with IBS find improvement in overall gastrointestinal symptoms, including abdominal pain, bloating, constipation, diarrhea, abdominal distention, and flatulence, following the diet 4.

Implementation and Monitoring

• Dietary counseling should be tailored to individual needs, and appropriate resources should be provided 3.
• A dietician should be involved in patients in whom a low FODMAP diet is planned to ensure a well-balanced diet and suitable alternatives with low FODMAP contents in each food group 2.
• Strict adherence to a low FODMAP diet is crucial for its success, and patients should be monitored regularly to assess symptom improvement and dietary adherence 3, 6.