According to the Association of German Pharmacists, the quality of food and drink directly affects the usefulness of medicine. Some drugs can affect the absorption of certain nutrients from food.
Grapefruit is one of the foods rich in healthy elements, but it can prevent the breakdown of many medicinal substances in the liver. Dairy products and mineral water contain calcium, which is important for bones, however, they directly affect antibiotics or osteoporosis medications, and therefore require separating their intake with a sufficient period determined by the doctor.