A warm bath before bed might feel like a simple luxury, but science shows it can also be a powerful tool for better sleep. The secret lies in how your body temperature changes when you step out of the tub.

The Temperature Connection

Your body naturally cools down in the evening as part of your circadian rhythm. This drop in core temperature signals that it’s time to sleep. Taking a hot bath or shower an hour or two before bed temporarily raises your body temperature. As you step out and begin to cool down, the rapid decrease mimics your body’s natural bedtime signal—making it easier to fall asleep.

Proven Sleep Benefits

Research shows that a pre-bedtime bath can:

  • Help you fall asleep faster
  • Improve sleep efficiency (the amount of time spent actually sleeping in bed)
  • Increase deep sleep, the most restorative stage of rest

It’s not the heat itself that makes you sleepy—it’s the cooling afterward that tells your brain it’s time to wind down.

How to Try It

  • Timing is key. Aim for 60–90 minutes before bedtime.
  • Keep it warm, not hot. About 100–104°F is ideal; too hot can be stimulating.
  • Make it relaxing. Dim the lights, add calming music, or try lavender bath salts for an extra soothing effect.

Beyond Baths

No tub? A warm shower, foot soak, or even a heating pad applied briefly before bed can have a similar effect.

By working with your body’s natural temperature rhythms, you can turn a nightly bath into a simple, science-backed sleep aid.