Milk and honey promote sleep

Milk and honey promote sleep. Milk contains tryptophan, an essential amino acid that is among the natural dietary sleep inducers.
Tryptophan works by increasing the amount of serotonin, a natural sedative, in the brain. This is why so many folk remedies include
warm milk with a teaspoonful of honey, a simple sugar. (Carbohydrates facilitate the entry of tryptophan into the brain.) A turkey
sandwich provides another sleep-inducing combination of tryptophan and carbohydrates. A banana with milk gives you vitamin B6, which
helps convert tryptophan to serotonin.
http://www.rd.com/living-healthy/sleep-and-diet-eating-to-sleep-well/article29172.html