Hot Bath Benefits for Sleep: The Science

5 Min Read | By Georgia Beech

Last Modified 30 October 2023   First Added 19 October 2023

This article was written and reviewed in line with our editorial policy.

A hot bath isn’t just a luxurious indulgence; it’s scientifically backed to help you get better sleep and improve your overall well-being. When you submerge yourself in the warm embrace of a bath, you’re not just unwinding, you’re also recalibrating your body’s inner clock. So. join us as we explore how to improve your sleep with a warm bath and the broader benefits of bathing.

How does a hot bath help you sleep?

Immersing yourself in a warming bath has long been considered to help with relaxation, and there’s scientific evidence to back the theory too. In analysis on the topic, Rajkumar Dasgupta, an active clinical researcher on sleep and other topics, is quoted on how heat improves sleep quality.

When people incorporate a warm bath into their bedtime routine, they affect their circadian rhythm by warming up their core body temperature before it cools down naturally in their sleep.

Circadian rhythms are a natural biological clock that helps regulate sleep. While these rhythms operate to respond to light and dark, they also trigger changes in body temperature.

Matthew Walker, author of Why We Sleep, discusses this further, identifying how your body’s core temperature needs to drop by roughly 2 degrees Fahrenheit to allow us to nod off. Other research found that warm baths increase blood circulation and move heat from the core to the hands and feet. This helps the body’s core decrease in temperature, preparing us for a restful sleep.

Woman in warm bubble bath reading

When is the best time to take a warm bath for sleep?

In a study conducted at the University of Texas, researcher Shahan Haghayegh states that you should bathe between 1-2 hours before bed. From the study, Haghayegh found that bathing a few hours before you plan to sleep can help you drift off ten minutes faster.

Is a warm bath good for sore muscles?

Soaking in a hot bath can also relieve muscle pain and promote relaxation. In 2016, a study conducted by Vienna Brunt explained how heat therapy increases blood flow and reduces arterial stiffness.

Furthermore, another study found that heat decreases muscle tension and spasms, making it an excellent solution for cramps. A hot bath is, therefore, a wise choice after an intense workout or to limit the impact of premenstrual cramps and injuries.

Man with flu symptoms

Is a hot bath good for a cold?

One of the most common symptoms of a flu or cold is nasal congestion. A stuffy nose can cause sleep problems, which can prolong your illness. Although a warm bath cannot cure this, it can ease the symptoms of a cold.

Steam is an effective way to release sinus pressure, improving your ability to breathe. Additionally, many physiologists have found that sweating is a great way to release toxins from the body, so a hot bath is an easy way to do this, especially if you are not ready for any strenuous exercise.

And given the improvements a hot bath can have for sleep and the wider benefits of sleep on our health, it works both ways. As Matthew Walker argues in Why We Sleep, sleep is essential for our well-being:

Without sleep, there is low energy and disease. With sleep, there is vitality and health.

Check out our article on how to sleep when you have a cold for more guidance.

Does a warm bath have mental health benefits?

Taking a bath is a great step towards self-care. Imagine scented candles, bath salts, and a book. Not only that, but a hot bath can also help balance serotonin levels and decrease stress.

A study found that those with depressive disorders had an improvement from regular bathing. During your self-care time in the bath, you could also practice mindfulness by focusing on your breath and the sensations of the warm water on your body. Amy Zack, MD says:

Baths also create a good environment for meditation, thought and escape from everyday stressors.

For more meditation tips and methods for calming down before bed, check out our 15 sleep relaxation techniques.

How to enhance your bath

There are many ways to add an element of luxury to your bath time. Consider a sprinkle of bath salts, a splash of bubble bath, or a twinkle of candlelight.

Close-up of hot bath with bath salts and lemon slices

1. Bath salts

For the ultimate relaxation Tim Hollinger, Co-founder of the Bathing Culture says that Epsom bath salts are a great way to relax the body. There are many bath salts to add to your experience. Sea salt possesses healing qualities with its rich minerals, which can be beneficial for muscle aches. Or simply choose a bath salt based on the scent. Indulge in a hot bath with lavender salts to eliminate your stresses.

Image of a woman in a bath blowing bubbles created by bubble bath.

2. Bubble bath

Pour in the bubbles and admire the scent as you unwind in your tub. The best thing about bubble bath is choosing the one that is right for you. Whether you’re looking to add moisture to your skin or intensify your relaxation experience there’s a bubble bath for all needs.

Image of two scented candles

3. Essential oils and scented candles

Add a drizzle of essential oils to your bath for an indulgent evening. For the right oil, consider what the aim of your bath is. The top three recommended oils for health and well-being are lavender, lemon and eucalyptus. You can also read our guide aromatherapy for sleep for more tips.

Image of several lighted candles against a dark black background

4. A calming ambiance

Consider playing quiet meditation music and dimming the lights to enhance the senses. Practice mindfulness by directing your attention to what you can smell, hear, and feel.

The humble hot bath offers more than just relaxation; it’s a scientifically proven elixir for a better night’s sleep. Although most studies do suggest more research is required, using a hot bath to control your body temperature can enhance your slumber, help relax sore muscles, and perhaps even help you find light relief from cold symptoms.

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