Up to 30% of individuals with Celiac disease experience ongoing abdominal complaints despite following a gluten-free diet. Here are some potential reasons, as noted in the scientific literature:
Inadvertent gluten exposure (up to 30% of cases)
Histamine intolerance
Lactose intolerance
Fructose malabsorption
Irritable bowel syndrome (often caused by SIBO and improved with low-FODMAP diet)
Eosinophilic esophagitis
H. pylori infection
Additional food sensitivities or allergies
Nickel sensitivity (improved with a low-nickel diet)
https://pubmed.ncbi.nlm.nih.gov/33833484/
https://pubmed.ncbi.nlm.nih.gov/33268003/
https://pubmed.ncbi.nlm.nih.gov/32751300/
https://link.springer.com/article/10.1007/s00394-020-02324-y
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