In the West, a glass of warm milk has a reputation for promoting sleep. Various studies have tried to prove this supposed virtue, but in reality, hot milk has no direct effect on sleep.
A good part of humanity is plagued by sleep disorders, whether it is dyssomnia (narcolepsy, insomnia) or parasomnia (sleepwalking, nocturnal bruxism) . Finding sleep is therefore a struggle for some people looking for solutions . Some practices aimed at "sinking" more easily into the arms of Morpheus consist of drinking herbal tea, having a light meal, placing sachets of lavender perfume near the pillow or even drinking hot milk.
It must be said that in our Western countries, drinking hot milk has the reputation to promote sleep. However, no clinical study has examined the effects of simple milk without addition. However, some have focused on milks with other ingredients. A publication by Agence Science-Presse of December 9, 2020 recalls the nature of this work.
In 1972, researchers evaluated the effect on sleep of Horlicks, a malted milk powder for hot drinks. According to the authors, the participants moved less in their sleep after taking this drink. However, the study had only four volunteers , i.e. too few to draw valid conclusions. Two years later, further work compared Horlicks to milk, a placebo and a flavored drink. According to the researchers, milk does not improve sleep conditions as the Horlicks might.
Other studies have dealt with the effectiveness of honey milk, and especially milk enriched with melatonin (sleep hormone). According to a study conducted in New Zealand in 2016, milk with melatonin has beneficial effects on people suffering from insomnia . On the other hand, the study was funded by the New Zealand dairy industry and the manufacturer of the famous fortified milk.
In reality, diet in general and eating habits have much more influence on sleep than some specific foods. So why do many people think hot milk has soporific properties? The reason lies in the presence of tryptophan , an amino acid. The latter is involved in the production of serotonin, a neurotransmitter linked to our moods and which in turn becomes melatonin.
Additional tryptophan is often prescribed to combat insomnia. However, the dose contained in a glass would not be sufficient to promote sleep . In short, hot milk has no direct effect on sleep seeking. However, unless you are lactose intolerant, nothing prevents you from drinking a comforting hot milk before sleeping.
