The consumption of gluten can cause a leaky gut, resulting in inflammation throughout the body. Gluten proteins intensify gut permeability by augmenting zonulin expression. Inflammation occurs as immune-stimulating compounds leak from the gut into the bloodstream. There has been a correlation between zonulin and mental illnesses such as autism, ADHD, and schizophrenia. Compared with non-anxious control subjects, anxiety patients with no history of gastrointestinal disturbances have shown to have elevated blood levels of zonulin. This means that gluten may be especially irritating to anxiety patients.