3 Phases of Implementing A Low FODMAP Diet

Have you ever heard of “FOADMAP”? It stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols, which are short-chain carbohydrates that are poorly absorbed in the small intestine and can cause digestive distress such as bloating, gas, diarrhea, constipation, and stomach pain. 

Diet low in FODMAP (the FODMAP diet) is usually recommended for people with IBS (irritable bowel syndrome), a common gastrointestinal disorder affecting an estimated 10-15% of the global population. Although the FODMAP diet is primarily designed for individuals with IBS and other gastrointestinal disorders, healthy individuals may also experience certain benefits by incorporating aspects of the diet.

The FODMAP diet is not meant to be a permanent diet but rather a structured approach that helps identify food triggers and allows for long-term symptom management. Introducing the FODMAP diet consists of three main phases:

Phase I: This phase lasts 4 to 6 weeks and involves completely removing all high-FODMAP foods (Table 1) from the diet. The goal is to reduce symptoms and establish a baseline of digestive health. Since FODMAPs are present in many foods, it requires careful planning and adherence to avoid unintentional consumption.

Phase II: Once symptoms have stabilized in Phase I, foods are systematically reintroduced one group at a time over a period of 6 to 8 weeks. This helps determine which FODMAPs trigger symptoms and at what quantity they can be tolerated. Each type of FODMAP is introduced individually to assess specific intolerances.

Phase III: After identifying personal triggers, a modified diet is adopted that includes only the tolerated FODMAPs while avoiding problematic ones. This ensures long-term symptom relief while maintaining a varied and nutritionally balanced diet.

Table 1. High-FODMAP and Low-FODMAP foods

Whilst it may not be easy to know the amount of FODMAP in each food items and food ingredients, several FODMAP certification programs exist to help consumers identify low-FODMAP products and ensure they are safe for individuals following a FODMAP diet. These programs test and certify food products to confirm their compliance with low-FODMAP standards, and logos are printed on the products. 

The FODMAP diet is a highly effective approach for managing digestive issues associated with IBS and other gut disorders. However, it is a complex diet requiring careful implementation. While it provides significant symptom relief for most people, it is not a permanent dietary plan. Instead, it serves as a tool to help individuals identify food triggers and create a sustainable, symptom-free eating pattern.

If you are considering a FODMAP diet, it is best to work with a healthcare provider or dietitian to ensure proper guidance and nutritional balance. With the right approach, the FODMAP diet can significantly improve digestive health and overall well-being.

References：

1.Gibson, P. R., & Shepherd, S. J. (2010). "Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach." Journal of Gastroenterology and Hepatology, 25(2), 252-258.

2.Staudacher, H. M., Whelan, K., Irving, P. M., & Lomer, M. C. E. (2012). "Dietary management of irritable bowel syndrome: A review of the evidence." Alimentary Pharmacology & Therapeutics, 35(5), 503-512.

3.Halmos, E. P., Power, V. A., Shepherd, S. J., Gibson, P. R., & Muir, J. G. (2014). "A diet low in FODMAPs reduces symptoms of irritable bowel syndrome." Gastroenterology, 146(1), 67-75.

4.Tuck, C. J., & Vanner, S. J. (2018). "Dietary therapies for functional bowel symptoms: Recent advances, challenges, and future directions." Neurogastroenterology & Motility, 30(1), e13238.

Editorial by Dr. Seiji Aoyagi

Dr. Seiji is the Chief Scientific Officer of NiHTEK & the owner and partner of GPNi Japan. He brings over 35 years of experience in clinical and sports nutrition, with publications in both the U.S. and Japan. He holds 4 nutrition patents, led the approval of HMB in Japan, and founded Total Nutrition Therapy to train physicians in clinical nutrition.