My Sleep Temperature Protocol
Hi friend,
A 9°F (5°C) increase in nighttime temperature cuts sleep by 23 min, which adds up to 6 days of lost sleep over a year.
That's what most people take in vacation days.
I've spent over 5 years becoming a professional sleeper. Temperature is the most underrated lever you can pull.
In this email:
- why sleep temperature is important
- how to stay cool
- my sleep temperature protocol
Why is sleep temperature important?
#1. Falling asleep
Your core body temperature needs to drop ~2-3°F (~1-1.5°C) to initiate sleep. Being too warm blocks that drop and may raise your heart rate before bed by 5 beats per min.
The result: it takes you longer to fall asleep.
#2. Deep sleep
The body wants to be at its lowest core temperature during deep sleep. This is the sleep stage when growth hormone is released, cellular repair happens, immune function is restored, and metabolic waste is cleared from the brain.
Heat exposure decreases deep sleep and increases wakefulness. 60-67°F maximizes deep sleep activity.
#3. REM sleep
Your body stops regulating temperature during REM, making it entirely dependent on the environment. This is the stage for memory consolidation, emotional processing, and cognitive restoration.
You want 68-72°F. Too warm and REM gets cut short. Too cool and it's disrupted.
#4. Waking up
Core temperature naturally rises in the early morning to prepare the body for wakefulness.
If you've had a hot, broken night of sleep, you'll wake up groggier than usual.
How to regulate temperature at night
- thermostat: Set your bedroom temperature between 60-67°F (15-19°C).
- bedding: Choose breathable bedding and sleepwear with natural fibers, like cotton or linen. If you sleep with a partner, use separate duvets to suit individual temperature needs.
- airflow: Use a fan or ventilate your bedroom.
- bath or shower: Take a warm bath or shower 1-2 hours before bed. The drop in body temperature afterward can help you fall asleep ~36% faster. It's also linked to deeper sleep and fewer awakenings. Note: I don't do this as my body temp falls naturally given my consistency in daily habits.
- Temperature-controlled mattress: I use Eight Sleep. It automatically cools to match the sleep stage you're in. Cooler for deep, restorative sleep. Slightly warmer to help protect REM without overheating.
My sleep temperature protocol
For optimum sleep, you need more than one steady temperature at night. I use Eight Sleep for this. It's one way I achieved 8 months of 100% sleep performance.
Why I like it:
- wide temp range: Cools to 55°F. Heats to 110°F. You don't have to rely on general temperature recommendations. Start with ~66-77°F and track your REM and deep sleep to find your ideal temperature. Adjust by a degree or 2 at a time. I've found 71°F for deep sleep and 73°F for REM sleep works best for me.
- auto adjusts during the night: This happens in real time based on your sleep stage and heart rate.
- thermal alarm: Gradual warming (nudging toward 72-75°F) works with your circadian rhythm to ease the transition out of sleep, reducing grogginess.
If you're considering it, you can get a discount on Eight Sleep if you purchase through Blueprint.
The most important thing: Take steps to cool your body before sleep and stop it from overheating at night.
Be well, Bryan
Bryan's product recommendations are just one part of his broader health routine. Individual results will vary, and the products alone should not be expected to reduce biological age. This content is for informational purposes only and is not medical advice. Consult your healthcare provider before starting any new wellness protocol. Blueprint may receive compensation from purchases made through partner links.
Originally published in Bryan Johnson's Blueprint newsletter (May 17, 2026). This content is for informational purposes only and is not medical advice.