Is it permissible to eat the food of non-People of the Book, such as the Yazidis?

The slaughtered animals of the Yazidis are not permissible, because they are not from the People of the Book. Whether a person among them is an original disbeliever who was raised on this belief, or an apostate who entered into it after embracing Islam, in both cases they are disbelievers or apostates.