If it comes in a can, in a box, in a bag, in a bottle, in a jar, in a carton, and you didn't put it there yourself; it isn't real food.
Real food is one ingredient, found in nature.
Fruit, Vegetables, Meat, Grain
All that other stuff that can be made by combining it is instantly suspect.
If it is made by you combining any of the above you are probably safe.
If it was made by a corporation, and you can't reproduce it in your kitchen using the basic equipment available to human beings, it isn't fit for human consumption.