Why Warm Milk Helps us Sleep Better

We all know age-old wisdom to cure sleepless nights– drink a glass of warm milk, but few of us know why milk helps us sleep better. What is in milk that makes it bed-time bliss? Does this natural soother work all the time?

Milk contains tryptophan, one of the ten essential amino acids that human body needs to synthesize proteins to maintain good health. Tryptophan facilitates the production of nervous system messengers related to relaxation, restfulness, and sleep. It also raises the level of serotonin, a neurotransmitter regulating our sleep patterns, appetite and mood. In order to deliver its soporific effect, tryptophan has to cross blood-brain barrier. It constantly competes with other amino acids to move across. Scientists at the Massachusetts Institute of Technology found that consuming protein-rich foods like milk and turkey reduces tryptophan’s ability to enter the brain. If there is not enough tryptophan in the brain, how can we sleep better.

Luckily, eating carbohydrates stimulates the release of insulin, which makes tryptophan enter the brain more easily. Drinking a glass of warm milk before bed can be a soothing routine, what really maximizes the sedative function of milk is a diet including high carbohydrates. Some people always feel drowsy after drinking a glass of warm milk, even though they do not eat any carbohydrate. This may have something to do with placebo effect.