Lack of adequate sleep is linked to many negative physical and mental health outcomes. It’s considered a major global public health issue.
According to the Centers for Disease Control and Prevention (CDC), 1 in 3 people in the United States alone doesn’t get enough sleep.
As a result, many people are seeking simple home remedies to improve the quality of their sleep patterns.
Having a glass of warm milk before bed is a tradition passed down through generations to cultivate relaxation, relieve anxiety, and facilitate a more restful night’s sleep.
Although many people swear by this practice, others say it’s nothing more than folklore.
This article reviews the science behind drinking milk before bed and whether it’s a practice worth adding to your bedtime routine.
Drinking milk before bed may help some people fall asleep faster
Some small animal and human studies demonstrate that consuming dairy products like milk and cheese before bed may help some people have a more restful night’s sleep, though the reason remains unclear.
Most experts agree that milk’s sleep-promoting potential is likely related to specific chemical compounds or the psychological effects of having a soothing bedtime routine — or perhaps a combination of the two.
It may promote healthy sleep cycles
Certain compounds in milk — specifically tryptophan and melatonin — may help you fall asleep.
Tryptophan is an amino acid found in a variety of protein-containing foods. It plays an important role in producing the neurotransmitter known as serotonin.
Serotonin boosts mood, promotes relaxation and is a precursor in the production of the melatonin hormone.
Melatonin, also known as the sleep hormone, is released by your brain. It helps regulate your circadian rhythm and prepare your body for entering a sleep cycle.
The role of tryptophan and melatonin in sleep disorders is well established. Studies have found that taking supplements of these compounds may improve sleep and reduce symptoms of anxiety and depression that can crop up at bedtime.
However, there’s currently no evidence to suggest that a single glass of milk contains enough tryptophan or melatonin to significantly influence your body’s natural melatonin production or to independently treat a disordered sleeping pattern.
Some experts suspect milk’s potential role as a sleep aid has little to do with its nutritional profile and that it’s more closely related to the psychological effect of having a calming bedtime ritual.
Another theory is that drinking warm milk could subconsciously remind you of having milk at bedtime during your early childhood years. These soothing feelings may signal to your brain that it’s time to sleep, making it easier to drift off peacefully.
Still, insufficient evidence guarantees any particular result from adding milk to your bedtime routine. More well-designed human studies are needed.
Summary: Milk contains several compounds that support healthy sleep cycles. Plus, the psychological effects of a bedtime routine that includes milk may improve your ability to fall asleep, but more research is needed.
Warm vs. cold milk for sleep
Proponents of consuming milk to induce sleep usually advocate for drinking it warm instead of cold, though there’s no clear evidence to indicate a major advantage of either method.
Most research evaluating the effects of drinking milk on sleep quality uses warm milk, and to date, there are no studies that compare the effects of different milk temperatures against each other.
That said, drinking a warm beverage — such as milk, tea, or something else — in the evening or during stress is a common cultural practice for alleviating anxiety and stimulating relaxation.
Warm liquids can have a calming effect on the nervous system and may be more effective for lulling you into sleep than cold drinks. However, results may depend on the individual.
Suggested read: 17 proven tips to sleep better at night
Any consistent bedtime ritual — whether it involves hot, cold, or no beverages — could benefit your sleep quality.
Summary: There’s no research comparing the effects of hot versus cold milk before bed, although warm beverages generally have more of a calming effect than cold ones.
Does drinking milk before bed affect your weight?
The health implications of eating right before bed are a complex topic with mixed evidence.
Firstly, drinking a glass of milk before bed is unlikely to cause any major changes in your weight, provided it’s not regularly contributing to large increases in your daily calorie intake.
That said, several studies have associated late-night snacking with weight gain. On the other hand, others have found various health benefits of consuming a bedtime snack in moderation.
Although there’s not yet enough evidence to establish a clear cause-and-effect mechanism, the relationship between meal timing — or in this case, milk timing — and weight management may be at least partially related to not getting enough sleep in the first place.
Poor sleep can increase cravings and snacking throughout the following day, potentially contributing to unhealthy weight gain over time.
Overconsuming calories just before bed may disrupt your circadian rhythm and further impair your ability to fall asleep, reinforcing this unhealthy cycle.
That said, a single 8-ounce (237-mL) glass of milk isn’t a significant source of calories and is unlikely to cause major disruptions in your circadian rhythm or weight.
If drinking milk helps you fall asleep faster or improves sleep quality, any observable weight changes could be related to the benefits of sleep and not the milk itself.
Summary: A single glass of milk at bedtime is unlikely to significantly affect your weight unless it causes you to dramatically overconsume calories.
Poor sleep is a major public health issue around the world.
Suggested read: 9 natural sleep aids: Melatonin & more, benefits, risks
Drinking a glass of warm milk before bed is a common practice to promote relaxation and support quality sleep.
Some studies indicate that milk may have sleep-promoting qualities for certain people, but more research is needed to understand how milk affects individual sleep cycles.
To date, no reliable evidence suggests that warm milk is better for sleep than cold, although warm beverages are generally used to alleviate anxiety and promote feelings of calm.
There’s no guarantee milk will improve your sleep, but if it’s a practice you’re interested in testing out, there’s no harm in trying.