People suffering from celiac disease are about 1% of the population, but until 12% reports having the same symptoms when eating bread, pasta, pizza and products derived from wheat: hence intestinal disorders, difficulty digesting, physical weakness e, in some cases, skin rashes.
In these cases, following a gluten-free diet does not solve the problem. Apparently, the enemy for these people is not a protein, like gluten, but the fruit, un carboidrato.
Fructan is a food that is part of the FODMAPs, short chain carbohydrates, which are not easily digested and ferment in our intestines, causing the irritable bowel syndrome that is, precisely, uno dei campanelli d’allarme per una sospetta intolleranza al glutine.
This carbohydrate, consisting of a long chain of fructose molecules, found in barley, rice and wheat, ma anche in alcuni vegetali e legumi come per esempio cipolle, ceci e carciofi.
Researchers from the University of Oslo and Monash University submitted 59 soggetti auto-diagnosticatisi la celiachia ad un interessante esperimento: for a few weeks the patients had to eat some bars without knowing if they contained gluten, fructan or a placebo, e annotare la comparsa e gravità dei sintomi.
Result? The bar containing gluten did not give any negative effects, while subjects subjected to fructan reported gastrointestinal symptoms similar to celiac disease (GSRS-IBS). This may explain why people who self-diagnose celiac disease without in-depth analysis, non riscontrano eccessivi miglioramenti dopo l’eliminazione del glutine.
Celiac disease is not an easy disease to diagnose, especially since the "definitive" test is a duodenal biopsy, therefore quite invasive; but the methods are there and are always better than self-diagnosis, che spesso causa più danni che benefici.
For more information on the symptoms and diagnosis of celiac disease: https://www.msdmanuals.com/it/casa/disturbi-digestivi/malassorbimento/celiachia