Food is an artifact type (like equipment, fortification, and vehicle) not a creature type. So no, changelings are not Food.
205.3g Artifacts have their own unique set of subtypes; these subtypes are called artifact types. The artifact types are Clue, Contraption, Equipment (see rule 301.5), Food, Fortification (see rule 301.6), Treasure, and Vehicle (see rule 301.7).
Artifact Creature - Food Golem
With the type Food showing up in the creature type bracket.
Does that mean Changelings count as food and can be used for cards like Wicked Wolf that interact with Food?
I realize they won't have the Food Token ruling of being able to sacrifice for 3 life. Just the type.
Does that mean Changelings are Cat Food?
205.3g Artifacts have their own unique set of subtypes; these subtypes are called artifact types. The artifact types are Clue, Contraption, Equipment (see rule 301.5), Food, Fortification (see rule 301.6), Treasure, and Vehicle (see rule 301.7).
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