Excessive feeding of milk and other dairy products can cause loose stools.
Raw liver or as much as three servings of cooked liver in a week can cause Vitamin A toxicity affecting the dog's muscles and causing deformed bones.
Onions & garlic:
Ingredients such as onions, garlic, milk and raw eggs used in home-prepared diets can cause illness or digestive trouble in cats and dogs.
Human foods used as treats such as chocolate, cakes and sweets containing the artificial sweetener xylitol and raisins and grapes can be toxic and therefore cause harm to cats and dogs.