The Science of How Warm Baths Promote Sleep

A hot shower or bath is the best way to get yourself feeling sleepy before bed

Many of us are used to starting our days by rushing into a piping hot shower. While this might seem like a good way to jolt us into our mornings, a warm shower or bath might actually be the best way to promote sleep before bed.

Studies have shown that increasing our body temperatures before bed can help us feel sleepier, leading to an easier time falling asleep, and a higher quality of rest once we do. A bath, warm shower, or even just running your wrists under warm water should be able to help you increase your skin and body temperature sufficiently to harness these effects.

However, it’s best if you time your bedtime shower properly in order to maximize your sleep. Aim to shower or bathe approximately an hour to an hour and a half before you intend to sleep.

The circadian rhythm – which controls our waking, sleeping, and eating cycles – is incredibly attuned to our body temperature. As our bodies cool down from a warm bath or shower, our circadian rhythm is signalled to begin making us sleepier. The drop in body temperature causes our body to slow down our heart rate, breathing rate, and digestion – getting our bodies into the perfect rhythm for optimal sleep. 

In hot climates, or during the summer, it may be difficult to get the natural drop in body temperature needed for good sleep. For this reason, it may be best to heat ourselves up, and set ourselves up for a decline in body temperatures in order to maximize sleep benefits. 

Bathing at night also has a number of other benefits. For example,  soaking in warm baths has been shown to reduce inflammation, and accelerate heart rate, which results in a modest yet tangible increase in calorie burn.