Other food sources of vitamin D include: 1  Cod liver oil (warning: cod liver oil is rich in vitamin A; too much may be bad for you) 2  Tuna canned in water. 3  Sardines canned in oil.  Milk or yogurt -- regardless of whether it's whole, nonfat, or reduced fat -- fortified with vitamin 1  D. Beef or calf liver.  Egg 1  yolks. Cheese.