Yes, radishes are naturally gluten-free. Gluten is a type of protein found primarily in wheat, barley, and rye. As a root vegetable, radishes don't contain these grains or any of their protein, including gluten. However, if radishes are prepared or cooked with sauces, dressings, or seasoning mixes that contain gluten, they would not be gluten-free. It's important to be aware of how your food is prepared if you're following a gluten-free diet.