Try not to eat eggs or milk with foods containing copper as the proteins in those foods can block absorption of the mineral. Also, try to cook foods as little as possible, using the minimum amount of water for boiling vegetables, to avoid leaching the copper into the water.Here are 6 foods that contain copper:eans and lentils are good sources of copper. They can be included in your diet through soups and salads, as well as burritos. Some other sources of copper include black pepper, mushrooms, dark leafy vegetables, barley and prunes.