Does a Bath Before Bed Help Sleep?

bath before sleep
A warm bath 1-2 hours before bed can help you get better quality sleep

If you struggle to get a good night’s sleep, there may be something you can do about it. Taking a hot bath before bed could help you sleep better. 

A research team led by Shahab Haghayegh reviewed 5,322 studies targeting data that linked bathing, water temperature and sleep quality. They published their findings in Sleep Medicine Reviews

One of their findings was that bathing 1-2 hours (ideally 90 minutes) before bed in water at a temperature of 104-109 F offered people best quality sleep. So taking a bath at that time and temperature may do the trick in helping you fall asleep about 10 minutes faster than usual.

How does a warm bath help sleep?

Our sleep and core body temperature are regulated by our body’s biological clock (circadian rhythm). In the late afternoon, our body temperature is about 2-3 degrees higher than at other times of the day. It drops by 0.5-1 F during bedtime and is the lowest during sleep. It starts increasing just as we prepare to wake up from sleep.

A warm bath or shower causes blood to circulate from the core of your body to your hands and feet, which can help lower your body temperature. So the idea is that once we increase our body temperature over 100 F, the body’s natural response is to make that temperature fall. This decrease in temperature mimics the natural decrease that happens when we sleep and signals the body to produce melatonin, which can help you fall asleep faster.

Why not a cold-water bath? Well, causing your body temperature to drop quickly can activate its fight-or-flight response. As a result, your body may become more alert instead of relaxed.

5 other tips for better sleep

Apart from getting a warm bath before bedtime, here are a few tips that may help you stay asleep throughout the night.

  • Stay away from blue light before bedtime: Switch off all electronics that emit blue light, such as smart devices and TV sets, one hour before bedtime. Digital screens can hamper your ability to sleep.
  • Do not have your dinner close to bedtime: Try to eat dinner at least three hours before bedtime. Having dinner late at night can activate your digestive system and keep you awake.
  • Avoid stimulants at night: Some people may have a habit of drinking coffee or other caffeinated drinks close to bedtime to keep them alert for a few hours. However, the effect of caffeine lasts for several hours, so try to avoid these types of drinks at least 3-4 hours before going to sleep. 
  • Do not take frequent naps: While taking a short nap (less than 30 minutes) in the afternoon is fine, taking frequent naps will disrupt your normal sleeping pattern.
  • Release stress before sleeping: Before getting into bed, let go of the stress and anxiety of the day—you can write them down on a piece of paper—and clear your mind of that day’s worries. This can prevent worries from getting in the way of your sleep.

QUESTION

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References
Haghayegh S, Khoshnevis S, Smolensky MH, et al. Before-bedtime passive body heating by warm shower or bath to improve sleep: A systematic review and meta-analysis. Sleep Med Rev. 2019 Aug;46:124-135.