Cow milk comes from cows and contains protein, lactose (a carbohydrate), fat, calcium, vitamin D, and B vitamins. People drink it plain, add it to cereal or coffee, and use it in cooking and baking.
Its complete protein aids muscle protein synthesis after exercise. The calcium and vitamin D support bone health. Many drink it with meals or as a snack, and choose reduced-fat or fortified versions to fit their diet.
Lactose can cause digestive distress in people with lactose intolerance. Those with a cow's milk protein allergy should avoid it. Calcium can reduce absorption of some antibiotics, like tetracyclines and fluoroquinolones. Space milk and these drugs apart by 2 to 4 hours.