ist reis glutenfrei oder nicht — what are common causes?

Rice is naturally gluten-free, as it does not contain gluten – a protein found only in certain grains like wheat, rye, and barley. However, in practice, contamination can occur. Common causes include cross-contact during farming, harvesting, transport, or processing (e.g., in mills that also handle gluten-containing grains). Packaged rice may contain trace gluten due to shared production lines. Additionally, rice dishes may be prepared with gluten-containing ingredients such as wheat flour coatings or broths. Consumers should look for certified 'gluten-free' labels, especially for processed rice products or restaurant meals. The evidence is strong: rice itself is gluten-free, but contamination risks are real and well-documented. The provided context does not contain specific information about rice, so this answer is based on general medical and food technology knowledge.