Protein contained in milk belongs to "high-quality protein", and its amino acid pattern is similar to that of human body, so it is easily absorbed by human body. Moreover, milk is also rich in calcium, which is a good calcium supplement.
These are just a few common nutrients: nutrient content: (fresh) milk (per 100ml): protein: 3.1g. Fat: 3.5 grams. Carbohydrate: 4.6 grams. Heat: 62 kcal. Inorganic salt: 7g. Calcium:120mg. Phosphorus: 90 mg. Iron: 0. 1 mg.
Milk is one of the oldest natural drinks, known as "white blood", and its importance to human body can be imagined.