What are the main sources of gluten?

The three main grains to avoid are:

• Wheat: Found in bread, pasta, cereals, crackers, and many baked goods. This includes all forms of wheat, such as spelt, farro, durum, and semolina.
• Rye: Found in rye bread, rye beer, and some cereals.
• Barley: Found in malt, barley flour, and barley flakes. It’s also a primary ingredient in most beers.