Milk contains two hypnotic substances:

1, tryptophan, can promote brain nerve cells to secrete the neurotransmitter serotonin that makes people sleepy.

2. It is a peptide that can regulate physiological functions. Among them, "opioid peptide" can combine with the central nervous system, which plays an anesthetic and analgesic role similar to opium, making people feel comfortable all over the body, which is conducive to relieving fatigue and falling asleep.

Extended data

The following people should not drink milk before going to bed:

1, kidney calculi patient. The most dangerous factor of stone formation is the sudden increase of calcium concentration in urine in a short time. Drinking milk for 2-3 hours before going to bed is the peak of calcium excretion in milk through the kidneys. At this time, it is in a state of sleep, urine is concentrated, and calcium passes through the kidney more, which is prone to stones.

2. People who lack lactase in their bodies. Everyone knows that this problem is also called lactose intolerance. The content of lactose in milk is so high that lactose cannot be directly absorbed by human body. It must be hydrolyzed into galactose and glucose under the action of lactase in digestive tract to be absorbed. Without lactase, lactose cannot be absorbed.

3. People who take iron drugs. When taking iron drugs to treat iron deficiency anemia, if you drink calcium and phosphorus in milk, it will combine with iron drugs and affect the curative effect.

People's health network-the role of milk in helping sleep. 10 people should not drink milk before going to bed.