Learning all the usual gluten-containing foods, such as breads and pasta, is only part of the challenge of going gluten-free. Gluten makes soups and sauces thicker and salad dressings creamier, keeps yogurt and soft cheeses firm and dried spices from clumping up, and it keeps candy bars from sticking to the factory conveyor belt. Gluten appears in the filler in pills and tablets and hides in lipsticks, toothpaste, and even mouthwash. If your celiac child is prone to putting everything in his mouth, you’ll also need to watch out for crayons and Play Doh, which also contain gluten. What’s more, even if gluten isn’t an ingredient in the product you’re purchasing, it might have gluten in it due to cross-contamination.