What role does tTG IgA play in blood sugar?

tTG IgA (tissue transglutaminase IgA) is an antibody used as a primary screening marker for celiac disease. Celiac disease is an autoimmune enteropathy triggered by gluten, leading to villous atrophy and malabsorption of nutrients, including iron, vitamin D, and carbohydrates. This malabsorption can indirectly affect blood sugar regulation, causing both hypoglycemic episodes (due to poor absorption) and postprandial hyperglycemia (due to altered gut motility and inflammation). Additionally, there is a well-established association between celiac disease and type 1 diabetes, with shared genetic risk (HLA-DQ2/DQ8). In individuals with diabetes, untreated celiac disease can lead to erratic blood glucose levels and increased hypoglycemia risk. However, tTG IgA itself does not directly modulate blood sugar; it is a diagnostic marker. Evidence: human-moderate (guidelines from ESPGHAN, ADA). Caveat: false negatives can occur in IgA deficiency; total IgA should be measured concurrently.