Low FODMAP Diet: A Review ★★★☆☆


Low FODMAP Diet: A Review ★★★☆☆

By R.Davies, PhD・Diet Atlas
Published on May 05, 2026


The low-FODMAP diet is designed to manage the symptoms of irritable bowel syndrome (IBS) and other gut health issues. ‘FODMAP’ is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are all basically types of carbohydrates that aren’t absorbed into your body very well, so they end up fermenting in your gut.

The diet was developed by researchers at Monash University (Australia) in the early 2000s, based on the understanding that (for some people) FODMAPs draw water into the gut and produce gas (through fermentation). In turn, this leads to gut issues such as bloating, abdominal pain, diarrhoea, and constipation.

The diet is typically conducted in three phases.

1. ‘Elimination Phase’ 

Involves avoiding high-FODMAP foods for 2-6 weeks. This includes avoiding certain fruits (e.g., apples, pears, watermelon), vegetables (e.g., onions, garlic, cauliflower), grains (wheat, rye), legumes, lactose dairy products, and sweeteners (e.g., honey, high-fructose corn syrup). During this phase, dieters are encouraged to consume low-FODMAP foods instead (e.g., bananas, oranges, carrots, potatoes, rice, quinoa, lactose-free dairy, and maple syrup).

2. 'Reintroduction Phase' 

Then tests individual FODMAP groups to identify triggers. This is done to create a long-term ‘modified’ FODMAP diet that only restricts problematic foods. 

3. 'Personalisation Phase' 

This means following a unique or personalised FODMAP diet, which means only avoiding foods that trigger symptoms. This is done to maximise dietary variety and flexibility of the diet whilst minimising symptoms. 



    Meal

    Example Foods & Dishes

    Breakfast

    Scrambled eggs with spinach & gluten-free toast

    Porridge made with lactose-free milk & blueberries

    Lunch

    Grilled chicken salad with lettuce, cucumber, carrots, & olive oil dressing

    Rice noodles with shrimp, bok choy, & ginger

    Snack

    Lactose-free yoghurt with strawberries

    Rice crackers with cheddar cheese

    Dinner 

    Grilled salmon with roasted potatoes & green beans

    Turkey meatballs with gluten-free pasta & tomato sauce (no garlic/onion)

    Dessert

    Dark chocolate (small portion)

    Drinks

    Peppermint tea, water, lactose-free milk


    Pros

    The low-FODMAP diet works well for improving IBS symptoms. Several high-quality studies show that the diet reduces abdominal pain, bloating and improves quality of life for most people with IBS. When properly supervised (by a qualified dietician), you can get all essential nutrients from low-FODMAP foods alone. The diet is also generally safe, with minimal negative effects.

    There is also some evidence suggesting potential benefits for other gastrointestinal conditions, such as inflammatory bowel disease. The structured, phased approach of the diet allows for personalisation, allowing you to expand the content of the diet while managing symptoms at the same time.

    Cons

    The low-FODMAP diet presents some practical and nutritional challenges. It is quite complicated to follow and will probably (for most people) require professional support to do it correctly. The FODMAP content of different foods isn't intuitive and requires a lot of research (or oversight/supervision). Prolonged or unsupervised restriction of FODMAP foods can potentially increase the risk of deficiencies (e.g., fibre, calcium, iron, zinc, folate, and certain vitamins).

    The diet's restrictive nature reduces food diversity and may negatively impact your gut microbiome, though long-term effects are unknown. Adherence to the diet can also be difficult due to higher food costs, limited availability of suitable products, and problems when dining out or attending social gatherings.

    Long-term safety data are limited, with most studies focusing on short- to medium-term outcomes. The diet is not recommended for people with (or at risk) of eating disorders, as its restrictive structure may exacerbate problems. Without proper guidance through the reintroduction phase, there is a risk that people may unnecessarily restrict foods, which could compromise nutrition, health outcomes, and quality of life.

    Bottom Line

    The low-FODMAP diet is an evidence-based, effective intervention for managing IBS and some other gut issues. However, it is not easy to follow, and (without professional supervision) there’s potential for nutrient deficiencies. This limits its practicality. So we think the diet is best suited for people who have IBS with medical oversight.


    Overall Score

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    Health Benefits

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    Nutrition

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    Weight Control

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    Ease to Follow

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    Safety Profile

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    Sources

    Bellini M et al. Low FODMAP Diet: Evidence, Doubts, and Hopes. Nutrients. 2020 Jan 4;12(1):148.PMID: 31947991

    Black CJ et al. Efficacy of a low FODMAP diet in irritable bowel syndrome: systematic review and network meta-analysis. Gut. 2022 Jun;71(6):1117-1126. PMID: 34376515

    Cox SR et al. Effects of Low FODMAP Diet on Symptoms, Fecal Microbiome, and Markers of Inflammation in Patients With Quiescent Inflammatory Bowel Disease in a Randomized Trial. Gastroenterology. 2020 Jan;158(1):176-188.e7. PMID: 31586453

    Staudacher HM, Whelan K. The low FODMAP diet: recent advances in understanding its mechanisms and efficacy in IBS. Gut. 2017 Aug;66(8):1517-1527. PMID: 28592442

    Whelan K et al. The low FODMAP diet in the management of irritable bowel syndrome: an evidence-based review of FODMAP restriction, reintroduction and personalisation in clinical practice. J Hum Nutr Diet. 2018 Apr;31(2):239-255. PMID: 29336079



    Published: May 05, 2026

    Lead Author: R.Davies, PhD | Author Bio

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