Home / Journal / Sleep Guides
Freezing Your Sheets and 6 Other Cooling Hacks, Checked Against the Evidence
Most viral cooling hacks feel wonderful for a few minutes and do very little by 3 a.m. Two of them are genuinely worth keeping: a fan, used sensibly, and a damp layer of skin or fabric in front of it. The rest are fine for getting to sleep on a hot night, and that's about it.
In this piece
- How We Rated Them
- The Quick Verdict
- Freezing Your Sheets
- Ice Packs, Cold Water Bottles and Rice Socks
- Fans, Airflow and the Damp-Towel Trick
- Cooling Pillows and Pillowcases
- Sleeping With Less, or Nothing
- The Two Hacks Worth Keeping (and What Actually Works All Night)
- Frequently Asked Questions
- The Bottom Line
If you want to know how to sleep cooler through the whole night, the answer is less exciting than the hacks. It's a cooler room, breathable bedding, and a warm bath an hour or two before bed. This guide rates seven popular tricks against that standard.
How We Rated Them
We couldn't find sleep studies on most of these hacks. Nobody has run a trial on frozen sheets. So the rating below is our judgment, based on a simple question: does the cooling last as long as you need it, or only for the first few minutes?
A cold object in your bed is a small store of cold. Your body is a steady source of heat. The object warms up, and once it reaches skin temperature it stops cooling you. Anything that relies on stored cold fades. Anything that keeps working, like moving air, lasts as long as it runs. Where real research exists, it's noted.
The Quick Verdict
| Hack | Verdict |
|---|---|
| Freezing your sheets | Fades fast. Helps you fall asleep, not stay asleep |
| Ice packs and cold water bottles | Fades fast. Useful in a heatwave |
| Frozen rice socks | Fades fast. Same idea, less mess |
| A fan | Keep. Works as long as it runs, in normal bedroom heat |
| Damp towel or sheet with a fan | Keep, in dry air. Weaker as humidity rises |
| Cooling pillows | Mostly a cool first touch. Fabric matters more |
| Sleeping with nothing on | Depends on you. Light sleepwear is steadier |
Freezing Your Sheets
The idea: put your sheets or pillowcase in a bag in the freezer for an hour, then make the bed. It feels lovely. It also stops working quickly, because a thin sheet holds very little cold and your body warms it within minutes. We found no study that measured how long it lasts, so we won't give you a number.
Where it helps: getting to sleep on a heatwave night, when the first few minutes in a hot bed are the hardest part. If falling asleep is your problem, it's a harmless trick. If waking hot at 3 a.m. is your problem, it won't reach that far.
Ice Packs, Cold Water Bottles and Rice Socks
A cold water bottle or wrapped ice pack at your feet, or a sock of rice that's been in the freezer, works the same way as frozen sheets: stored cold that runs out.
You'll often read that ice on your "pulse points" cools your whole body. We couldn't find good evidence for that in sleep. What is well supported is that your hands and feet are where the body sheds heat at night, so cooling your feet can feel good and may help you settle. Our guide to why you sleep hot after 40 explains why the hands and feet matter.
Always wrap ice packs in a cloth. Direct ice on skin for long periods can damage it.
Fans, Airflow and the Damp-Towel Trick
A fan is the hack most worth keeping. Moving air carries heat away from your skin and helps sweat evaporate, which is how the body cools itself. Unlike a frozen sheet, it keeps working for as long as it runs.
There is one important limit. In heat-chamber studies at very high temperatures, fans stop helping and can even make things worse for older people. A 2017 trial in Medicine & Science in Sports & Exercise exposed young and older adults to 42°C (about 108°F) with humidity rising from 30% to 70%. The fan made no real difference for young adults, but in adults with an average age of 68 it slightly raised heart rate and core temperature. A 2025 study of 18 older adults (average age 72), sitting for eight hours at 36°C (about 97°F), found that fans failed to meaningfully reduce physical strain.
Those are temperatures far above a normal bedroom, even on a warm night. In ordinary summer heat, a fan pointed at your body is a cheap and sensible help. In a genuine heatwave, especially if you're older, a fan isn't enough on its own. Find a cooler room, or air conditioning, and drink water.
The damp-towel trick adds water to the fan. You drape a damp towel or sheet over yourself, or simply dampen your arms and legs, and let the fan blow across it. As the water evaporates, it takes heat with it. Sports research supports the principle. In a 2017 study of simulated tennis in hot, humid conditions (36°C or 97°F, 50% humidity), wetting the skin in front of a fan cooled players about as well as iced towels. A companion study in very dry heat found a fan only worked when the skin was wet.
The limit is humidity. Evaporation slows as the air gets more humid, so the trick works best in dry heat and fades in muggy weather. A 2012 review in the Journal of Physiological Anthropology noted that humid heat adds to the body's heat load during sleep. If your bedroom is humid, a dehumidifier or air conditioning will do more than a damp towel.
Cooling Pillows and Pillowcases
Most "cooling" pillows feel cold when you first lie down. That first-touch coolness comes from the material drawing heat from your skin, and it fades as the pillow warms to your temperature. We couldn't find independent sleep research showing that gel pillows keep you cooler through the night.
What matters more is whether the pillowcase and pillow let heat and moisture escape. A breathable natural weave on a pillow that doesn't trap heat will usually serve you better than a gel layer. Our guide to which sheet fabric sleeps coolest explains which fabrics breathe and which hold sweat.
Sleeping With Less, or Nothing
Some hot sleepers swear by sleeping naked. Others find they wake up stuck to damp sheets. We found no sleep research comparing the two, so this one comes down to you.
If you sweat at night, light sleepwear in a fabric that handles moisture can be steadier than bare skin, because it gives sweat somewhere to go. If you don't sweat much, less may genuinely feel cooler. Try each for a few nights and notice how you feel at 3 a.m., not just at bedtime.
The Two Hacks Worth Keeping (and What Actually Works All Night)
Keep the fan. Point it at your body, not your face if dry eyes bother you, and use it in ordinary warm weather.
Keep the damp-towel trick for dry, hot nights. It's free and the physics is sound.
For cooling that lasts the whole night, the real fixes are less dramatic:
- A warm bath one to two hours before bed, which helps your body shed heat on schedule. See warm bath before bed.
- A cooler room. Our guide to the best bedroom temperature has the research-backed range.
- Breathable bedding and a lighter duvet.
Frequently Asked Questions
Does freezing your sheets help you sleep? It can help you fall asleep on a hot night, because the first few minutes feel cool. The cold fades quickly as your body warms the fabric, so it won't help with waking hot later in the night.
Is it better to sleep with a fan on? For most hot sleepers in ordinary warm weather, yes. Moving air helps sweat evaporate. In extreme heat, studies show fans alone may not be enough, especially for older adults, so a cooler room or air conditioning matters more.
Does a wet towel cool you down at night? Yes, with a fan and in dry air. Evaporating water carries heat away. The effect weakens in humid weather, when water evaporates more slowly.
Should you sleep naked if you sleep hot? It depends. Some people feel cooler. Others wake up damp because sweat has nowhere to go. Light, breathable sleepwear is a steadier option if you sweat at night.
What actually cools you all night? A cooler bedroom, breathable bedding, a fan, and a warm bath one to two hours before bed. Most frozen or chilled hacks only help for the first few minutes.
The Bottom Line
The hacks that rely on stored cold, like frozen sheets, ice packs and rice socks, help you get to sleep and then run out. A fan keeps working, and a damp layer in front of it works even better in dry heat. For the whole night, the boring answers win: cool the room, lighten the bed, and take a warm bath earlier in the evening.
Sources
Retrieved October 2026.
- Gagnon D, Romero SA, Cramer MN, Kouda K, Poh PYS, Ngo H, Jay O, Crandall CG. Age modulates physiological responses during fan use under extreme heat and humidity. Med Sci Sports Exerc. 2017;49(11):2333-2342. doi:10.1249/MSS.0000000000001348 (abstract via PubMed)
- Lee BJ, et al. Effect of pedestal fan use on serum stress biomarkers in older adults exposed to simulated daylong indoor overheating. Physiol Rep. 2025;13(12):e70390. doi:10.14814/phy2.70390 (abstract via PubMed)
- Schranner D, et al. In-play cooling interventions for simulated match-play tennis in hot/humid conditions. Med Sci Sports Exerc. 2017;49(5):991-998. doi:10.1249/MSS.0000000000001183 (abstract via PubMed)
- Lynch GP, Périard JD, Pluim BM, Brotherhood JR, Jay O. Optimal cooling strategies for players in Australian Tennis Open conditions. J Sci Med Sport. 2018;21(3):232-237. doi:10.1016/j.jsams.2017.05.017 (abstract via PubMed)
- Okamoto-Mizuno K, Mizuno K. Effects of thermal environment on sleep and circadian rhythm. J Physiol Anthropol. 2012;31(1):14. doi:10.1186/1880-6805-31-14 (abstract via PubMed)
Educational only. This article is not medical advice, and nothing in it is a substitute for talking to a clinician about your own sleep. Last reviewed October 2026.
