It is not permissible to consume foods, drinks and medicines that contain gelatin derived from the skin of pigs or other impure substances. It is possible to manufacture gelatin from animals that are slaughtered in the prescribed manner, and it will serve the same purpose in manufacturing medicine or food. For more, see the detailed answer.

It is not permissible to eat from the food which the Christians or non-Muslims prepare on Christmas or other festivals. It is also not permissible to accept their invitations to join them in their celebrations.