Morning and evening are the best time to drink milk, and drinking milk for breakfast provides sufficient nutritional guarantee for the vitality of the day; Drinking milk at night not only helps you sleep, but also helps your body absorb nutrients. According to the research of American and British medical experts, milk contains two hypnotic substances that were not known before. One of them is tryptophan synthesized by serotonin, which can promote sleep. Because of its function, people often only need a glass of milk to fall asleep. The other is natural morphine, which has similar anesthetic and sedative effects. Therefore, if you drink milk in the morning, it will inevitably inhibit people's cerebral cortex and affect work and study during the day. In addition, drinking milk in the morning is not conducive to digestion and absorption. This is because protein in milk can only be absorbed by human body after it is decomposed into amino acids in stomach and small intestine. In the morning, on an empty stomach, the stomach empties quickly, so the milk is discharged into the large intestine and has not been digested. Furthermore, protein absorbed in food can only form a part of human tissues on the basis of sufficient calories. If the heat is insufficient, the absorbed protein will soon become heat and be consumed, which is undoubtedly a waste of overqualified materials. Therefore, nutrition experts believe that it is best to drink milk at night or half an hour before going to bed. Milk is rich in nutrition, which not only contains essential amino acids, but also contains high-content and easily absorbed calcium. Drinking it for a long time is very beneficial to your health. However, you must pay attention to the way you drink milk. The following are common misunderstandings about drinking milk. You must pay attention to avoid that drinking milk on an empty stomach will increase intestinal peristalsis, shorten the retention time of milk in the stomach, and make the internal nutrients not be fully absorbed and utilized. It is best to drink milk with some starchy foods, such as steamed bread, bread, corn porridge and beans, which are beneficial to digestion and absorption. Improper food collocation Milk should not be eaten with foods containing tannic acid, such as strong tea and persimmons. These foods easily react with milk and agglomerate, which affects digestion. Like highly processed milk. The nutritional value of highly processed milk is not necessarily better than that of fresh milk. This is because after many times of processing, trace elements or inorganic salts are mostly added to milk, but these ingredients do not need to be supplemented by everyone, so they are not necessarily suitable for everyone. Knowledge of drinking milk Some people will have stomach growling, bloating, abdominal distension and diarrhea after drinking milk. This is because milk contains a kind of lactose. After birth, lactase in the intestine decomposes lactose in milk at the lactation stage of infants, and lactose will ferment and decompose in the large intestine to produce water, carbon dioxide and lactic acid. Lactic acid is not easily absorbed by human body. Carbon dioxide is a gas, which can cause flatulence, abdominal pain, bowel sounds, diarrhea and other symptoms. What should adults do if they have this symptom after drinking milk? 1, pay attention to drink less, or drink a small amount of milk several times, and drink half a bottle at a time (1.20 ml). After drinking 1.2 months, the activity of lactase in the intestine may increase again, and there will be no symptoms of bowel sounds and diarrhea after drinking again. Eating milk and eggs together is also a way. After the milk is heated, add the raw eggs and stir them. Eat them when they are half cooked. Eggs are most easily digested when they are half-cooked. This way of eating has complementary functions in both digestion and nutrition. Who shouldn't drink milk? 1, people who lack lactobionic acid can't drink milk. Milk has a high lactose content and cannot be directly absorbed by the human body. It must be decomposed into galactose and glucose under the action of lactobionic acid in the digestive tract before it can be absorbed. If lactobionic acid is deficient, eating milk will cause abdominal pain and diarrhea. 2. Lead workers should not drink milk. Lactose in milk can promote the absorption and accumulation of lead and aggravate or cause lead poisoning. 3. After patients with iron deficiency anemia take iron supplements, if they drink milk, calcium and phosphate in milk will hinder the absorption of iron. 4, some patients with digestive tract diseases can't drink milk, milk can promote gastric acid secretion, thus aggravating and inducing digestive tract diseases. Therefore, patients with ulcerative colitis, reflux esophagitis, cholecystitis, pancreatitis and total gastrectomy had better not drink milk. In addition, there are some common sense about milk: milk should not be cooked for a long time or overheated. A series of changes will take place when milk is heated. When heated again after boiling, lactose in milk will start to coke and gradually decompose into lactic acid and a small amount of formic acid, vitamins will be destroyed, and even the color, smell and taste will be significantly reduced. So hot milk is just cooked, so it should not be cooked for a long time. Milk should not have too many cold drinks. Because cold milk will increase gastrointestinal peristalsis and cause mild diarrhea, especially for patients with gastrointestinal diseases such as ulcers and colitis, it will aggravate the condition. And most of the nutrients in milk can't be used. Milk should not be frozen or stored in a thermos. After freezing, the fat, protein and other substances in milk have changed, and after thawing, there will be solidified precipitation and floating lipid precipitation, which will reduce the nutritional value. Therefore, it is appropriate to store milk at about 3℃. When the milk is hot, pour it into a thermos for preservation. Bacteria can easily mix into milk. Once bacteria enter milk, they can reproduce every 20 ~ 30 minutes, which makes milk deteriorate rapidly. Drinking milk at night is better than drinking it in the morning. It is reported that drinking milk before going to bed has hypnotic effect. Medical scientists have observed that drinking a cup of hot milk before going to bed can make people fall asleep quickly and sleep sounder after midnight, especially for some people who can't sleep after waking up in the middle of the night. Because milk contains L- tryptophan which makes people feel tired and morphine which has sedative effect. If you drink milk in the morning, it will definitely affect your study and work during the day, so it is better to drink milk at night. It is best not to drink milk on an empty stomach. Some people like to drink milk on an empty stomach in the morning. In fact, this is unscientific, because eating on an empty stomach makes the stomach peristalsis faster, and the nutrients in milk are discharged to the large intestine before being digested and absorbed, resulting in a large loss and waste of nutrients. Therefore, it is best to drink milk before eating steamed bread and biscuits, so that the nutrients in milk can be fully exerted. Bottled milk has been sterilized during processing, so it is not necessary to boil it when drinking. Boiling will denature protein, and calcium and phosphate will be destroyed and lose their nutritional value. If milk is kept for a long time, it will go bad because of the reproduction of bacteria. Drinking spoiled milk will not only increase nutrition, but will cause diseases. Therefore, it is best to drink milk.