Gluten and risk of Type 1 diabetes

The role of gluten in Type 1 Diabetes has been in the spotlight again this week with a research report in Diabetologia showing that a child’s intake of gluten at age 18 months is associated with a 46% increased risk of developing type 1 diabetes for each extra 10g of gluten consumed.

This is not the first time that gluten has been linked to increased risk in Type 1 Diabetes. A review (Antovorskov et al 2014) in the same journal in 2014 reviewed earlier studies that showed the highest incidence of type 1 diabetes in experimental animal models is found in animals on a wheat-based diet, and a cereal-based diet promotes type 1 diabetes development in both NOD (non obese diabetic) mice and BB (biobreeding) rats. This suggests a clear correlation between gluten intake and increased diabetes susceptibility.

Other research has shown that an abnormal mucosal immune response to gluten is present in at least a subset of type 1 diabetic patients. The association may simply reflect the common genetic background of celiac diease and type 1 diabetes; however, the studies reporting a specific immune response to gluten in type 1 diabetic patients without celiac disease-associated HLA-haplotype suggest a direct, diabetes-specific effect of gluten.

Evidence points toward the involvement of the intestinal immune system in the development of type 1 diabetes and studies suggest that pancreas-infiltrating autoreactive T cells may be activated in the gut-associated lymphoid tissue (GALT). Research also suggests that zonulin upregulation is associated with increased intestinal permeability in a subgroup of type 1 diabetic patients. Zonulin upregulation seems to precede the onset of the disease, providing a possible link between increased intestinal permeability, environmental exposure to non–self antigens, and the development of autoimmunity in genetically susceptible individuals.

Studies in human subjects have reported that upon stimulation with wheat proteins or their components, patients with T1D showed a heightened proliferative T cell response as compared to control patients.

A recent research piece in JAMA Pediatrics by Hakola et al (2019) concluded that a high intake of oats, gluten-containing cereals, gluten, and dietary fiber was associated with an increased risk of islet autoimmunity which would then be implicated in Type 1 Diabetes. There is strong evidence that removal of gluten from the diet can selectively be protective against development of diabetes.