A gluten-free diet (GFD) is a diet that excludes gluten, a protein composite found in wheat, barley, rye, and all their species and hybrids (such as spelt, kamut, and triticale). The inclusion of oats in gluten-free diet remains controversial. Avenin present in oats may be also toxic for coeliac people. Its toxicity depends on the cultivar consumed. Furthermore, oats is frequently cross contaminated with gluten-containing cereals.