Gluten is primarily found in wheat, barley, and rye. Many common foods contain gluten, including bread, pasta, cereals, baked goods, and some processed foods. It's essential to read labels carefully and be aware of hidden sources of gluten, such as certain sauces, dressings, and processed snacks. Opt for naturally gluten-free whole foods like fruits, vegetables, lean proteins, and whole grains like quinoa and rice to build a foundation for your healthy gluten-free diet.