Science Focus - the home of BBC Science Focus Magazine
Does warm milk help you sleep? © Getty Images

Does warm milk help you sleep?

Published: 24th March, 2017 at 14:00
Subscribe to BBC Science Focus Magazine and get 6 issues for just £9.99

No drinking milk and driving! Breaking news: Santa Claus takes the risk of falling asleep at the wheel of his sleigh.

Asked by: Thomas Mitchell, Chelmsford


Warm milk may be soothing, but the jury is out on its soporific qualities. Milk contains a protein called alpha-lactalbumin, a source of the amino acid tryptophan. This forms serotonin, a neurotransmitter that helps to regulate mood and sleep. Consuming alpha-lactalbumin increases blood levels of tryptophan.

However, research shows that a large dose is required to give enough tryptophan for the desired effect. Milk also contains a bioactive peptide, casein hydrolysate, which is thought to have anti-stress properties, while magnesium could help with restless legs.

A Dutch trial on 15 women with insomnia suggests that milk may improve sleep, especially when enriched with magnesium and the protein casein hydrolysate.


Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.


Dr Emma Davies is a science writer and editor with a PhD in food chemistry from the University of Leeds. She writes about all aspects of chemistry, from food and the environment to toxicology and regulatory science.


Sponsored content