Celiac disease: “gluten-free”, no easy ride for the gut
For people with celiac disease, one year on a gluten-free diet does improve overall well-being – but it also depletes the gut microbiota, and 1 in 3 patients continue to suffer from gastrointestinal symptoms. Could pairing it with prebiotics and synbiotics be the solution?
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About this article
When you have (sidenote: Celiac disease A disease caused by a malfunction of the immune system, which mistakenly attacks normal components of the body – in this case, the small intestine. It is triggered by the ingestion of gluten in genetically predisposed individuals. ) , there is no debate: (sidenote: Gluten Gluten (from Latin glue): a viscous nitrogenous substance formed when flour is hydrated. It originates from specific proteins – glutenins and gliadins – found in cereals, primarily wheat. ) has to go. But what really happens inside the gut after a year on this diet? What are the effects on the gut microbiota? Do symptoms persist? A recent UK study 1 took a closer look at these questions.
1% Prevalence of celiac disease in the general population ranges from 0.5% to 2%, with an average of about 1%. ²
2 to 3 As with other autoimmune diseases, celiac disease is more common in women, who are affected 2 to 3 times more frequently than men. ³
Before going gluten-free, both gut and patient suffer
Before starting their gluten-free diet, patients with celiac disease already show significant differences: low mood, digestive symptoms and less hydrated stools – despite water content in the small intestine being unusually high. In particular, intestinal transit is much slower. The likely culprits? Mucosal lesions in the intestinal wall, which affect water absorption and secretion, and probably also chronic inflammation and some hormonal imbalances in the digestive system.
Digestive disorders
One year gluten-free: better, but far from perfect
Good news first! After one year on a gluten-free diet, patients generally feel better. Anxiety is reduced and gut transit accelerates slightly. But it’s not a cure-all; their well-being still lags behind that of people without celiac disease, and some continue to experience celiac-related symptoms.
The diet also takes a toll on the microbiota, in other words the community of bacteria living in our intestines. Removing wheat and its by-products (bread, pasta, biscuits, etc.) cuts out not only gluten, but also the fibers derived from this cereal and consequently the beneficial bacteria like Bifidobacteria that feed on these fibers. Instead, this diet seems to stimulate the bacteria associated with protein breakdown, such as E. coli and Peptostreptococcus, which we’d rather not encourage.
Celiac disease, wheat allergy, hypersensitivity to gluten: know the difference! 6,7
Gluten is not “toxic” for the general population; it is well tolerated by most people. However, it’s involved in two very different conditions:
- Celiac disease: an autoimmune disorder (the immune system attacks its own body) that occurs weeks to years after gluten exposure. It causes lesions in the small intestine lining. It is diagnosed by the presence of auto (sidenote: Antibodies Antibodies are described in the study as key biological markers for diagnosing and monitoring celiac disease. ) in the blood;
- Wheat allergy: a classic allergic reaction that occurs within minutes or hours after contact with gluten or other wheat proteins. It triggers an immune response on the part of the body along with the release of histamine. Prevalence varies from 0.5% to 9% in children and 0.4% to 1% in adults, depending on the study.
What if the diet isn’t enough?
Another striking finding: 1 in 3 patients report persistent or even worsening gastrointestinal symptoms despite strict gluten avoidance. Specific fatty acids and the presence of certain bacteria in the gut microbiota may explain the persistence of these symptoms.
While strict gluten elimination remains essential for managing celiac disease, this study shows that it’s not always enough. The next step may be to include targeted (sidenote: Prebiotics Prebiotics are specific indigestible dietary fibres which have effects that are favourable to health. They are used selectively by the beneficial micro-organisms in the microbiota of individuals. Specific products combining probiotics and prebiotics are known as symbiotics. Gibson GR, Hutkins R, Sanders ME, et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics. Nat Rev Gastroenterol Hepatol. 2017;14(8):491-502. Markowiak P, Śliżewska K. Effects of Probiotics, Prebiotics, and Synbiotics on Human Health. Nutrients. 2017;9(9):1021. ) (fibers that nourish good bacteria) or synbiotics (blends of pre- and probiotics), to help support a healthier microbiota – and potentially greater digestive comfort. This could benefit even those patients whose antibody levels have normalized, which is a marker of effective immune response to the diet.
What is the difference between prebiotics, probiotics and postbiotics?
2. Catassi C, Verdu EF, Bai JC, Lionetti E. Coeliac disease. Lancet. 2022 Jun 25;399(10344):2413-2426.
3. Malamut G, Cellier C. Place et bilan de la maladie coeliaque. Hepatogastroenterology, 2012;19:597-606.
5. EU Regulation No. 1169/2011 on the provision of food information to consumers (“INCO” Regulation).
