Does warm milk before bed help you sleep?

Drinking a glass of warm milk before you go to bed at night is not just an old wives’ tale – there’s some real science behind this common bedtime ritual.

“Milk can potentially help a person sleep because it contains the amino acid tryptophan, a precursor to serotonin,” says Becky Kerkenbush, a registered dietitian and media representative for the Wisconsin Academy of Nutrition and Dietetics. “We can thank serotonin for milk’s snooze-inducing properties. Serotonin is a neurotransmitter that plays a role in appetite, sleep, behaviour, mood, body temperature and coordination.”

Kerkenbush adds that milk is also a rich source of calcium, which helps muscles relax. Milk also has a soothing effect when warmed up and may evoke comforting childhood memories.

According to mattressadvisor.com, one cup of 1% milk has 12 grams of carbs and 8 grams of protein, which makes it a sleep superstar. Milk also has 12 amino acids (milk has 12), including tryptophan. When tryptophan enters the bloodstream, the body turns it into a B vitamin called Niacin, which helps to produce serotonin. Serotonin is a neurotransmitter that aids in melatonin regulation, aka the sleep hormone. So, tryptophan before bed means better sleep too.

One hitch is that for tryptophan to enter the bloodstream it needs to be accompanied by complex carbohydrates (found in whole foods, like bran, barley and rolled oats). Consider having your glass of milk with an oatmeal biscuit or a muesli rusk.

If you don’t drink milk, you can try other sleep-friendly options, like tart cherry juice (rich in melatonin) or a magnesium supplement.

For more expert sleep advice, visit our Sleep Blog.