How Temperature Affects Your Sleep

Room temperature is one of the most important—and often overlooked—factors in sleep quality. Too hot or too cold, and you'll struggle to get restful sleep. Here's what science tells us about temperature and sleep.

Why Temperature Matters for Sleep

Your body temperature naturally drops as you prepare for sleep. This drop signals to your brain that it's time to release melatonin and initiate sleep.

If your bedroom is too warm, it interferes with this natural cooling process. Your body can't drop to its optimal sleep temperature, making it harder to fall asleep and stay asleep.

The Science of Body Temperature and Sleep

Your Daily Temperature Rhythm

Your body temperature follows a circadian pattern:

• Afternoon: Temperature peaks (around 2-4pm)
• Evening: Starts to decline as bedtime approaches
• Night: Drops 1-2°F during sleep (lowest around 5am)
• Morning: Rises to help you wake up

How Temperature Affects Sleep Stages

• Falling asleep: Requires a drop in core body temperature
• Deep sleep: Occurs when body temperature is lowest
• REM sleep: Body loses some ability to regulate temperature, making environment more important

The Ideal Bedroom Temperature

The sweet spot: 60-67°F (15-19°C)

Most sleep experts recommend keeping your bedroom in this range. The most commonly cited optimal temperature is 65°F (18°C).

Why So Cool?

A cool room:

• Supports your body's natural temperature drop
• Signals to your brain that it's time for sleep
• Allows for comfortable sleep under blankets (which provides security and comfort)
• Reduces night sweats and sleep disruptions

When It's Too Hot

Sleeping in a room above 75°F (24°C) can:

• Reduce total sleep time
• Decrease deep sleep and REM sleep
• Increase wakefulness during the night
• Cause night sweats and discomfort

When It's Too Cold

While less common, sleeping in a room that's too cold can also disrupt sleep by:

• Making it hard to relax muscles
• Causing discomfort that leads to waking
• Making it difficult to get out of bed in the morning

Tips for Optimal Sleep Temperature

Bedroom Environment

• Set your thermostat: Program it to 60-67°F before bed
• Use a fan: Circulates air and provides white noise
• Open a window: If outdoor temps are cool enough
• Use blackout curtains: Blocks heat from sunlight during the day
• Consider a cooling mattress pad: Actively regulates bed temperature

Bedding Choices

• Breathable sheets: Cotton, linen, or bamboo are best
• Layered bedding: Easily adjust by adding or removing layers
• Cooling pillows: Gel-infused or ventilated designs
• Light comforter in summer: Switch to a warmer one in winter

Body Cooling Strategies

• Take a warm bath or shower: Counterintuitively, this helps—as you cool afterward, it signals sleep time
• Wear light, breathable sleepwear: Or sleep naked if comfortable
• Cool your feet and hands: Exposing extremities helps release heat
• Avoid heavy exercise close to bed: Raises body temperature
• Stay hydrated: Helps regulate body temperature

Special Considerations

Hot Sleepers

If you naturally run hot:

• Aim for the lower end of the range (60-65°F)
• Invest in cooling mattress technology
• Consider moisture-wicking sleepwear
• Keep a fan pointed at your sleeping area

Cold Sleepers

If you naturally run cold:

• Aim for the higher end of the range (65-68°F)
• Use warmer bedding
• Wear socks to bed (warm feet help you fall asleep faster)
• Consider a heated mattress pad on low

Sleeping with a Partner

Different temperature preferences? Try:

• Separate blankets with different warmth levels
• Dual-zone heating/cooling mattress pads
• Compromising on room temperature while adjusting personal bedding
• A bed fan for the warmer sleeper

Hot Flashes and Menopause

Night sweats can severely disrupt sleep. Consider:

• Cooling mattress pads and toppers
• Moisture-wicking sheets and sleepwear
• Keeping a fan nearby
• Having a cool glass of water by the bed
• Lower room temperatures

The Warm Bath Sleep Hack

Taking a warm bath 1-2 hours before bed is one of the most effective ways to improve sleep onset. Here's why it works:

1. Warm water dilates blood vessels in your hands and feet
2. When you get out, your body rapidly releases heat through these dilated vessels
3. This accelerates the natural temperature drop that signals sleep
4. Studies show this can help you fall asleep 36% faster

The ideal timing is about 90 minutes before bed.

Temperature and Sleep Quality Summary

• Keep bedroom between 60-67°F (15-19°C)
• Use breathable bedding and sleepwear
• Take a warm bath 1-2 hours before bed
• Keep extremities (feet) warm to help release core body heat
• Avoid exercise close to bedtime
• Adjust based on personal preference and season