Sleep Better by Staying Cool: How Temperature Affects Your Sleep

We spend a lot of time talking about mattresses, pillows, supplements and bedtime routines. But one of the simplest things that can affect sleep is often overlooked:

Temperature.

Your body temperature naturally changes throughout the day, and those changes are closely tied to your sleep-wake cycle. As bedtime approaches, your body begins to cool down. Creating the right environment can help that process along—and may make it easier to fall asleep and stay asleep.

Why Your Body Cools Down at Night

In the evening, your core body temperature gradually begins to fall.

At the same time, more blood flows toward the skin, particularly the hands and feet. This helps your body release heat and is part of the normal transition toward sleep.

That’s one reason a bedroom that feels too warm can make it harder to sleep comfortably. Your body is trying to cool down while the environment is working against it.

You don’t need to focus on an exact thermostat number. What matters more is that your bedroom feels comfortably cool without feeling cold.

If you regularly wake up sweating, throw the covers off during the night or feel uncomfortably warm in bed, temperature may be playing a role.

A Warm Shower Before Bed Can Actually Help

It may seem strange that warming yourself before bed could help when your body is trying to cool down.

But a warm shower or bath can increase blood flow to the skin. Afterward, your body can release heat more easily, which may help with the natural drop in core temperature that happens before sleep.

A good approach is to take a warm shower or bath roughly one to two hours before bedtime.

It doesn’t need to be extremely hot. The idea is simply to warm the skin and then give your body time to cool naturally before you get into bed.

Your Sheets Can Make a Difference

The temperature of your bedroom is only part of the story.

Your sheets, blankets and pajamas create their own small environment around your body. If they trap too much heat and moisture, you can feel hot even when the room itself is fairly cool.

If you tend to sleep warm, look for lightweight, breathable bedding.

Cotton and linen are both reasonable choices. Linen in particular tends to breathe well and may be comfortable for people who sleep hot.

But I wouldn’t get too caught up in claims that one particular fabric is the “best” for sleep. There isn’t enough evidence to say that everyone needs linen, bamboo, Tencel or any other specific material.

The simpler rule is better:

Choose sheets that feel light, breathable and comfortable to you.

The weight and weave of the fabric may matter just as much as the material itself.

What About Your Mattress?

Your mattress can also affect how warm you feel during the night.

Traditional memory foam tends to mold closely around the body and may retain more heat than some other mattress designs. That doesn’t make memory foam bad—it just means some people who naturally sleep hot may find it less comfortable.

Latex mattresses and mattresses that use coils or hybrid construction generally allow more airflow. Some newer foam mattresses are also designed with ventilation, open-cell foam or other cooling features.

If you already have a mattress that is comfortable and you sleep well, I wouldn’t replace it simply because another material is advertised as “cooling.”

But if you are shopping for a new mattress and you know that you tend to sleep hot, breathability is worth considering along with comfort and support.

Cooling mattress toppers and other temperature-control products may also make the bed feel more comfortable, although the evidence that they actually improve sleep itself is still limited.

And Yes, Socks May Help Too

Here’s an interesting part of the temperature story.

Although your core body temperature is dropping as you prepare for sleep, having warm hands and feet may actually help that process by allowing your body to release heat through the skin.

That means if you get into bed with very cold feet, warming them may make it easier to settle down.

There has even been a small study suggesting that wearing socks to bed may help people fall asleep faster and sleep a little longer.

The research is limited, so I wouldn’t consider socks a treatment for insomnia.

But if your feet are often cold at bedtime, there is little downside to trying a pair of soft, loose, breathable socks and seeing if you feel more comfortable.

The goal is warm feet—not hot or sweaty feet.

A Few Simple Things to Try

If you think temperature may be affecting your sleep, start with the basics:

• Keep your bedroom comfortably cool.
• Avoid heavy bedding if you tend to sleep hot.
• Choose lightweight, breathable sheets and sleepwear.
• Consider a warm shower or bath an hour or two before bedtime.
• If your feet are cold, try sleeping in comfortable socks.
• If you're buying a new mattress and tend to sleep hot, consider materials and designs that allow better airflow.

You don’t need to do all of these things at once. Sometimes one small adjustment is enough to make your sleep environment more comfortable.

Temperature Is Only One Part of Good Sleep

Getting the temperature right can help, but it won’t fix every sleep problem.

If you regularly have trouble falling asleep, wake repeatedly during the night or feel tired despite spending enough time in bed, there may be another reason.

Insomnia, sleep apnea, restless legs, circadian rhythm problems, medications and other medical conditions can all interfere with healthy sleep.

In those situations, changing your sheets or lowering the thermostat may help with comfort—but it probably isn't the whole answer.

The Bottom Line

Temperature plays an important role in the way your body prepares for sleep.

As bedtime approaches, your body naturally begins to cool. A comfortably cool bedroom, breathable bedding and a warm shower before bed can all help support that process.

And if your feet tend to be cold?

A pair of socks may be worth trying too.

You don't need to turn your bedroom into a sleep laboratory. Start by making it cool, comfortable and breathable and see how you sleep.