Review article: safe amounts of gluten for patients with wheat allergy or coeliac disease

Abstract

SUMMARYFor both wheat allergy and coeliac disease the dietary avoidance of wheat and other gluten-containing cereals is the only effective treatment. Estimation of the maximum tolerated amount of gluten for susceptible individuals would support effective management of their disease.Literature was reviewed to evaluate whether an upper limit for gluten content in food, which would be safe for sufferers from both diseases, could be identified. When setting gluten limits for coeliac disease sufferers, the overall potential daily intake should be considered, while for wheat allergy limits should be based on single servings. For coeliac disease sufferers this limit should lie between 10 and 100 mg daily intake. For wheat allergy, lowest eliciting doses for children lie in the lower milligram range, while for adults they are most significantly higher.Gliadins (part of the gluten proteins) not only trigger coeliac disease, but are also major allergens in wheat allergy. Therefore, measurement of gliadins with validated enzyme-linked immunosorbent assay methods provides an appropriate marker for assessing gluten and/or wheat protein contents in food. Available data suggest that a maximum gluten content for 'gluten-free' foods could be set, which protects both wheat allergy sufferers and coeliac patients.

Gliadins in Foods and the Electronic Tongue

“…Therefore, foods that contain wheat starch should be labeled as "low-gluten" (Fasano and Catassi, 2001). The proposed standard as formulated by the WHO/FAO organization Codex Alimentarius, has one limit at 0.02% for "rendered gluten-free" food, and another at 0.002% for "naturally gluten-free food" (Bai et al, 2013;Hischenhuber et al, 2005;Niewinski, 2008). These different practices reflect the fact that we do not know the exact limit of gluten intake that is tolerated long term without harmful effects by patients with celiac disease as a group (Ciclitira et al, 2005a).…”

“…These different practices reflect the fact that we do not know the exact limit of gluten intake that is tolerated long term without harmful effects by patients with celiac disease as a group (Ciclitira et al, 2005a). The acceptable gluten dose per day is still under debate, although the scientific and medical communities have suggested that around 50 mg/day is safe (Hischenhuber et al, 2005). As a reference, the normal gluten intake by healthy individuals is about 13 g/day (Van Overbeek et al, 1997).…”

“…Although a gluten-free diet is prescribed to patients suffering from diseases related to gluten exposure, this does not mean that they cannot tolerate gluten at all, as their clinical sensitivity varies significantly (Ciclitira et al, 2005a;Hischenhuber et al, 2005). Some individuals cannot tolerate trace amounts of gluten, whereas others appear to tolerate large amounts.…”

Celiac disease diagnosis and gluten-free food analytical control

“…The European Union, World Health Organization, and Codex Alimentarius require reliable measurement of the wheat prolamins, gliadins, rather than all wheat-derived proteins [84]. There is still no general agreement on the analytical method to measure gluten in ingredients and food products [85], although the official limits described in the Codex Draft Revise Standard (2000) are 20 ppm for foodstuffs naturally gluten-free and Never-theless, to measure gluten traces in food, immunochemical methods are usually chosen to determine gliadins [87][88][89][90][91][92]. Besides the quality control of gluten-containing products, it is important to assess gluten in foodstuff that can be contaminated with native or heated proteins from wheat, barley, and rye.…”

The role of processing and the food matrix in allergenicity of foods

“…The modified peptides are able to bind to class II human histocompatibility leucocyte antigen (HLA) molecules DQ2 and DQ8. This recognition event appears to orchestrate an abnormal cellular-mediated immune response which triggers an inflammatory reaction which results in the flattened mucosa characteristic of Coeliac's disease (Hischenhuber et al, 2006).…”