For Better Sleep, Cool Your Body Temperature

People often wonder how room temperature is associated with sleep quality. Here is a quick Q&A on the topic.

Q: How is body temperature related to sleep quality?

A: Your body temperature must drop to fall and stay deeply asleep. Otherwise, you will stay in light sleep and keep waking frequently during the night. Leaving you exhausted the next day. Part of this is because the drop in body temperature triggers both melatonin release and the calming part of your nervous system (called the parasympathetic nervous system).

Q: What is the ideal body temperature for sleep?

A: The optimal core body temperature for this is 96.8°F to 97.4°F

Q: What factors influence nighttime body temperature?

A: Room temperature plays a modest role in this, and it is recommended to set your thermostat to 60-67° at night when you sleep. Ironically, you want your skin to stay warm, so blood goes to your arms and feet, which then acts like a radiator to whisk the heat away. Paradoxically, this "radiation" actually lowers your core body temperature. So a colder room is not really better.

Q: Do Apple Watches that monitor body temperature as part of sleep tracking help. If so, why?

A: Unfortunately, the Apple Watches monitor the skin temperature, not your internal organ core body temperature. So this is not especially helpful.

Q: How do you advise people maintain an ideal sleep temperature overnight?

A: Very simple measures can help people maintain lower core body temperatures and improve sleep:

1. Take a sustained release melatonin (I like Melatonin EP120™ 10 MG Sustained Release, which is what I take each night). This easily and significantly lowers core body temperature. The sustained release allows it to continue working through the night.
2. Wearing warm socks during sleep has been shown to help people fall asleep more quickly and stay asleep deeper and longer. Why? Warming the feet causes blood to go to the feet, radiating off the heat and paradoxically cooling down your core body temperature.
3. Similarly, it helps to take a hot shower or bath 90 minutes before bed. As with wearing socks, heating your skin causes blood to go to your hands and feet. After a bath, your blood quickly cools, dropping your internal core heat and accelerating sleep onset. Want to make this even more effective? Add one to two cups of Epsom salts (magnesium) to your bathwater. This will relax your muscles while also easing pain, facilitating sleep even further.
4. Use breathable sheets that are cooling, like cotton, bamboo, or linen.
5. If you have severe sleep issues due to problems regulating body temperature during sleep (and you have plenty of extra spending money), the Eight Sleep Pod 4 can be very helpful. It has an intelligent "Autopilot AI" that automatically adjusts the mattress temp on your side of the bed to keep you in deep sleep. It can separately do this for both people in a bed, so everyone can be comfortable.