Does Warm Milk Help You Sleep?

April 2, 2024 | Casper Editorial Team

Fact checked by Jonathan Eilenberg, CPE

Yes, drinking warm milk before bed may help you sleep better. Milk’s sleep-enhancing properties are commonly ascribed to tryptophan, an amino acid that can help the body produce sleep-promoting serotonin and melatonin. Additionally, scientists have discovered a mixture of milk peptides that relieves stress and enhances sleep.

It’s a cultural trope that’s appeared time and time again in cartoons, books, and movies: someone having trouble sleeping turns to a comforting glass of warm milk. 

Because of this ever-present cliché, we take for granted that warm milk can cure even the most stubborn insomnias. But does warm milk help you sleep, or is this just a myth?

According to some scientific studies, milk does contain certain compounds that may relax your body and help you drift off when you can’t sleep. But does it have to be warm to work, and what if you’re lactose intolerant? Fortunately, we’re here to answer all these questions, and more, so that you can find the best nightly beverage for sleep support.

The Science Behind the Glass

To understand the effects of sipping on a warm glass of milk before bed, we’ve turned to scientific literature that’s been compiled on the topic, from direct studies of the effect of warm milk on sleep quality to analyses of milk’s chemical and nutritional composition. 

Speaking of composition, let’s start by exploring three compounds within milk that may play a role in promoting better sleep.


Tryptophan may be the most famous essential amino acid of the twenty or so most common ones in the human body. While it’s present in many foods, tryptophan often gets blamed for the sleep-inducing effects of Thanksgiving turkey. Because tryptophan is also present in milk, it makes sense that the beverage might have the same drowsy effects on people who consume it.


Recent studies have shown that casein, a major protein in cow’s milk, is broken down by the body into a number of different peptide compounds that have the potential to cause anxiolytic and soporific effects.1 In non-science language, this means that these compounds may help ease anxiety and introduce feelings of sleepiness, causing you to relax and fall asleep faster. 

Does Milk Have To Be Warm to Help You Sleep?

While many studies have looked into the potential benefits of milk as a sleep aid, few have compared the effects of milk consumption at different temperatures. This makes it hard to say whether your nightly glass has to be warm to be effective.2 Most people simply choose to drink it warm because drinking a warm liquid (like milk or tea) is a common relaxation practice.3

Instead, warm milk’s effectiveness is likely that it works as a placebo, like with any consistent bedtime routine. Placebos do work, however, so if you’ve found that warm milk helps you drift off into restful sleep better than cold milk, there are few reasons to stop turning to it.

Potential Downsides of Drinking Milk to Help Sleep

While warm milk is popular and easily accessible as a potential sleep aid, some people are unable to take advantage of this beverage or may be better off without it.

Allergies and Intolerances

Milk is one of the most common allergens for children, affecting up to 3% of young people.4 An even greater proportion of people are afflicted with lactose intolerance, the inability to digest milk. For these sensitive groups, a soothing nocturnal treat can turn into an unpleasant trip to the bathroom—or even the hospital. 

Dietary Considerations

Other people, like vegans, have ethical or lifestyle concerns about the consumption of dairy products. The food and beverage industry has also been turning away from cow’s milk, with many people opting for soy milk, oat milk, or almond milk as plant-based alternatives instead. 

Health Considerations

Warm milk can certainly be a toasty, tasty tipple for the end of the night, but it isn’t necessarily a diet-friendly or low-calorie choice. Those watching their weight might want to default to skim milk instead. 

Non-Dairy Alternatives for Better Sleep

Whether you’re lactose intolerant, follow a plant-based diet, or just looking for a lower-calorie option, the following beverages may be just what you’re looking for:

Herbal Tea

Herbal tea, unlike its black and green tea counterparts, does not contain any caffeine, making it a great option for your pre-bedtime routine. Plus, some teas have been shown to have sleep-promoting benefits, such as5

  • Chamomile
  • Lavender
  • Lemon balm

Plant-Based Milk

No matter how popular they get, milk alternatives cannot replicate the tryptophan content of cow’s milk. However, drinking a warm glass of plant-based milk can have the same soothing effect as a nighttime ritual that traditional dairy milk does. 

Sleep Better with Casper

While studies show that warm milk can potentially help with sleep, the tasty beverage is only part of the equation—Casper can provide you with the rest. 

From innovative mattresses to comfortable sheets and plush pillows, Casper’s extensive line of sleep products is designed to enhance your sleep, night after night. 

Plus, with fast shipping, a 100-night risk-free mattress trial, and a 10-year limited mattress warranty, you can rest easy in dairy-filled bliss knowing that your sleep hygiene is in the most capable hands with Casper.

For the extra-curious, does tart cherry juice help you sleep too? Find out in our blog.


  1. American Chemical Society. Warm milk makes you sleepy — peptides could explain why.
  2. Sleep Doctor. Does Warm Milk Help You Sleep? 
  3. Healthline. Should You Drink Milk Before Bed?
  4. Encyclopedia of Food Sciences and Nutrition. Milk Allergy.
  5. Sleep Foundation. The Best 7 Teas for Sleep. 
  6. New York Times. The Claim: A Glass of Warm Milk Will Help You Get to Sleep at Night.