“If you want to sleep well, take a proper soak in the tub instead of just showering.”
It’s advice many of us have heard for years, but what is the actual relationship between bathing and sleep?
In August 2026, a research team from Shanghai University of Sport and other institutions published a systematic review and meta-analysis of 10 randomized controlled trials on immersing the body in warm water and sleep.
The results suggest that warm-water bathing may improve total sleep time and sleep efficiency.
What 2026 Research Revealed About Bathing and Sleep
This study analyzed 10 randomized controlled trials involving healthy adults.
When people immersed their bodies in warm water (“warm-water immersion”),
• Total sleep time increased
• Sleep efficiency improved
These were the trends the analysis found.
Sleep efficiency is the percentage of the time spent in bed that you are actually asleep.
For example, even if you spend eight hours in bed, your sleep efficiency will be low if you wake up many times during the night.
These results suggest that bathing may not simply help you “sleep longer,” but may help you spend more of your time in bed actually sleeping.
On the other hand, for some measures, such as how long it takes to fall asleep and how well people felt they slept, no clear improvement was found.
In other words,
“A soak in the tub will always give you a deep night’s sleep”
is not something this research can claim.
Why Does a Bath Make It Easier to Fall Asleep?
A key factor in understanding sleep and bathing is changes in body temperature.
At night, our “core body temperature,” the temperature inside the body, gradually falls.
This drop in temperature is part of how the body prepares for sleep.
When you soak in warm water, your body first warms up and blood flow increases to the hands, feet and other extremities.
Then, after you get out of the bath, heat escapes from the body more easily, and your core body temperature begins to fall.
This sequence of “warming up, then releasing heat” is thought to possibly help the natural transition into sleep.
So rather than heating your body intensely right before bed, the key is to leave a little time before going to sleep.
If You Take a Bath, Aim for 1 to 2 Hours Before Bed
Several studies on bathing and sleep were conducted even before 2026.
A 2019 systematic review by a research team from the University of Texas and other institutions in the United States reported that bathing in water of about 40 to 42.5°C (104 to 108.5°F) 1 to 2 hours before bedtime may help people fall asleep and improve sleep efficiency.
And you don’t need to soak for a long time; in the research, there were cases where benefits were seen with baths or showers of about 10 minutes or more.
In other words, if your goal is better sleep,
rather than “taking a long, hot bath,” warming your body at a moderate temperature and allowing time for your body temperature to fall before bed
appears to be what matters most.
That said, very hot baths above 42°C (about 108°F) put a greater strain on the body.
To avoid feeling lightheaded or becoming dehydrated, there’s no need to push the temperature higher or stay in the bath for a long time.
We Can’t Yet Say “A Bath Is Always Better Than a Shower”
This is an important point to keep in mind when reading this research.
The 2026 study mainly looked at warm-water bathing, in which the body is immersed in warm water.
So from this study alone,
“A bath is better for sleep than a shower”
is not a conclusion we can draw.
Past research has also reported positive effects on sleep from warm showers.
Rather than an either-or choice between “bath or shower,” it seems better to think in terms of
warming the body moderately
→ then allowing time for the heat to escape
→ and creating an environment that makes it easy to fall asleep
as the steps that matter.
Of course, taking a slow soak in the tub also creates a moment that marks “the end of the day’s activities,” which is a big benefit as a daily habit.
Sleep Isn’t Determined Only After You Get into Bed
When we think about sleep quality, we tend to focus only on our bedding or how many hours we sleep.
In reality, though, how you spend the 1 to 2 hours before sleep also matters.
Working late into the night, staying glued to your smartphone, spending time in a brightly lit room.
Rather than going straight from that state into bed, creating a routine like
taking a bath
dimming the lights a little
putting your smartphone away
letting your body rest slowly
can make it easier to prepare yourself for sleep.
If you have mostly been taking quick showers lately, you might start by trying a slow soak in the tub at a comfortable temperature 1 to 2 hours before bed.
At La HEAD, we carefully care for not only the head but also the neck and shoulders, and we value giving you time to step away from the tension of the day and relax.
When you want to improve your sleep, try looking not only at “how many hours you slept,” but also at how you rest your body and mind before sleep.