FODMAP intolerance

FODMAPs is the acronym for: fermentable oligo-, di- and monosaccharides and polyols. FODMAPs are a group of carbohydrates found in certain foods. For some people they can be difficult to digest and cause gastrointestinal discomfort. If FODMAPs are not broken down properly in the small intestine, they enter the large intestine where they are fermented by intestinal bacteria. This produces gases that can lead to flatulence, abdominal pain, diarrhea or constipation. Symptoms vary from person to person and many do not know that they suffer from FODMAP intolerance.

FODMAP intolerance manifests itself in non-specific gastrointestinal symptoms. These include, for example, abdominal pain, diarrhea, constipation, abdominal bloating, nausea and vomiting. Apart from these digestive symptoms, extraintestinal symptoms may also occur. These include headache, dizziness, memory impairment, lethargy, cognitive dysfunction, muscle and/or joint pain, skin lesions, mouth ulcers, palpitations, eczema and urticaria.

Symptoms usually occur a few minutes or hours after consuming FODMAPs. In some cases, however, there are also late reactions, which further complicates the diagnosis of intolerance.

Diagnosing FODMAP intolerance can be complex as the symptoms can be similar to other gastrointestinal disorders. The first step is to keep a food diary to identify links between the foods eaten and symptoms experienced. Some people seek support from a nutritionist or gastroenterologist to get a professional diagnosis. An important aspect of this is the elimination diet, which involves avoiding all FODMAP-rich foods for a certain period of time. FODMAPs are then gradually reintroduced to identify which specific groups or foods are causing individual problems.

Common nutrient deficiencies in untreated celiac disease include iron, B12, calcium, vitamin D and zinc. For most CD patients, a strict GFD should result in complete resolution of their symptoms. On a low FODMAP diet, the risk of fiber, calcium, protein, iron and vitamin B12 depletion is well known and the role of a trained dietitian should be considered fundamental.

Foods with a low FODMAP content are for example:

• broccoli
• fennel
• cucumber
• potatoes
• carrots
• zucchinis
• yellow peppers
• red peppers
• blueberries
• passion fruit
• grapes
• oats
• spelt
• Oat milk

Foods with a high FODMAP content are e.g.:

• cauliflower
• green peppers
• mushrooms
• beet
• asparagus
• onions
• garlic
• apples
• Blackberries
• cherries
• mango
• Peach
• Watermelon
• Wheat
• Cow's milk
• honey
• Coconut blossom sugar

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