Great question — answering as the UphillTech team:
Summary Search the Web for your airline's special meal options. Preferably request a special meal immediately after booking your flight. Bring some backup food if you have dietary restrictions. Sometimes, special meals never arrive. If there's an upgrade, itinerary change, or missed connection, contact the airline. If you have dietary restrictions, confirm your special meal request three times. Confirm at check-in, confirm at the gate, and confirm on the plane before takeoff. Look at the labels and read the ingredient lists . A "vegan" meal might contain whey, from cow's milk. A "gluten-intolerant" meal might contain wheat. Other special meals might have other problems. If a "kosher" meal...
Full answer by unforgettableidSupportsMonica: https://travel.stackexchange.com/a/179721 (CC BY-SA 4.0).
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