What are cool pillows?

Just like your mattress and your bed base, your pillow also has an important function: supporting your neck and head. Logical! Of course, there are characteristics that additionally play a major role in helping you fall asleep quickly. Consider, for example, firmness, moisture regulation and heat regulation. Can a pillow have a cooling effect? And which materials are then more or less suitable? We dive in deeper.

How does a cooling pillow work?

Or rather, how does cooling work? Cooling is a feeling that is temporary. Because what you actually want is climate regulation around your head. That way you won’t be too hot or too cold. Strong heat-insulating materials will raise the temperature around your head faster than materials that disperse heat optimally.

Wool is a natural material with a powerful effect. This natural hair from sheep, camels or goats quickly takes over the temperature of your head and will also try to maintain it. You might expect to get too hot pretty quickly for this reason. Thanks to the powerful moisture-regulating properties that wool has, the heat is also distributed well over your pillow. Therefore, it is perfectly suited if you get hot quickly.

Synthetic materials such as hollow polyester fibers retain insulation around your head and therefore can feel “sweltering” faster.

Why are cold pillows better than normal pillows?

So cold pillows are relative, because a ‘cold’ pillow is temporary. Your head is going to give heat to the pillow. More important is how the pillow handles this. Spreading heat is top notch! And powerful heat diffusion often has the property of making a pillow feel temporarily colder.

A cool-to-the-touch pillow can be pleasant if you feel hot when going to bed. Japanese studies using (actively) cooled pillows found that people in a warm, humid bedroom woke up less often and sweated less (Okamoto-Mizuno et al., 2003), and young women slept more deeply and comfortably with them (Hamanishi et al., 2019). Whether a cool pillow actually helps you fall asleep faster has, as far as we know, never been researched. This has been studied for mattresses, however: in sleep labs in Germany, Italy, and the United States, 72 people slept on a mattress with a top layer capable of absorbing and dissipating significant body heat, at a normal bedroom temperature of 21 to 23 °C. Their core temperature dropped slightly further, their hearts beat more calmly, and they gained an average of about 7 to 8 minutes of extra deep sleep per night (Herberger et al., 2024). That is a small but measurable effect, measured on an entire mattress rather than a pillow, and even there it wasn’t proven that people fell asleep faster. Good to know: all these studies used a mattress from one and the same brand, and the manufacturer collaborated on part of the research and also partially funded it.

Gel conducts heat much better than foam or fibers. It quickly dissipates heat from your skin and therefore feels cool, just as a metal plate feels colder than a wooden block at the same temperature (Sleep Foundation, 2026). The more gel there is, the more heat it can absorb before it reaches your body temperature. A thick gel layer will therefore continue to feel cool for longer than a thin layer.

Fabrics containing viscose or those enriched with so-called PCMs also offer a (seemingly) cooling effect. PCM stands for phase change material. These are tiny capsules containing a waxy substance, often a paraffin, that melts at a temperature close to your skin temperature. According to the Belgian textile producer Devan, which incorporates such capsules into fabrics, the material absorbs heat as it gets warmer, stores it temporarily, and releases it again as soon as it cools down. French textile researcher Fabien Salaün (ENSAIT) describes the same principle but also points out the limit: the capsules only work as long as they are melting and stop as soon as everything has melted. A thin layer can therefore only absorb a limited amount of heat, making the cool sensation primarily noticeable shortly after you lie down.

Are cooling pillows good for you?

Your core body temperature (CBT) follows a daily rhythm: in the evening, around the time you go to sleep, it drops, and once you are asleep, it drops a bit further. Japanese sleep researchers Okamoto-Mizuno and Mizuno describe this in their 2012 review study. You fall asleep most easily while that temperature is falling. This causes your body to use less energy, your heart rate to drop, and your body to settle down.

Note: your core temperature is not the same as your skin temperature. Around bedtime, the blood vessels in your hands and feet open wider. Your skin there becomes warmer and releases heat, which helps your core cool down. Swiss research by Kräuchi and colleagues (2000) showed that this heat dissipation via hands and feet was a better predictor of how quickly someone fell asleep than the core temperature itself.

The point is that the temperature or sleep climate remains well-regulated and aligned with your body temperature. If you get too hot, you wake up more often and get less deep sleep and REM sleep. This is evident from the review study by Okamoto-Mizuno and Mizuno (2012). Especially stuffy, humid heat in the first part of the night plays tricks on you. You then go looking for a cooler spot and wake up briefly.

Different types of cooling pillows in a row

What choices can you make to sleep cool on your pillow?

1. Animal materials like wool, camel hair or cashmere are powerful in moisture management and heat insulation. So they are going to help regulate your body temperature nicely.
2. Plant materials such as linen, lyocell or wild silk are powerful in ventilation and moisture management. That’s how you keep your cool.
3. Synthetic materials such as Thinsulate fibers are lab-designed fibers that closely approximate the properties of wool. So suitable!
4. Foams such as gel are not heat insulating and thus will have a powerful thermoregulatory effect. Your body temperature will be optimally regulated.
5. Use an additional cooling protective pad made of material containing viscose or PCM-enriched materials.

What is the coolest pillow?

Try for yourself in the store to see what works best for you! In any case, most pillows are not actively cooling. The material reacts to your body temperature. Of course, there are actively cooling pillows. The disadvantage is often that they are connected to a device that actively cools and are therefore tied to an electrical outlet. There is also a chance that you will find the noise disturbing.

Is there a pillow that is always cold?

When you work with filling materials, you don’t. Even a gel pillow with a thick layer of gel takes on your body temperature over time as you sleep. And that’s fine!

Frequently Asked Questions:

What are cool pillows – Conclusion

Focus on climate regulation around your head. That way you won’t be too hot or too cold. Strong heat-insulating materials will make the temperature around your head rise faster than materials that disperse heat optimally.

Resources

1. Okamoto-Mizuno K, Mizuno K (2012). Effects of thermal environment on sleep and circadian rhythm. Journal of Physiological Anthropology, 31, 14. doi.org/10.1186/1880-6805-31-14
2. Kräuchi K, Cajochen C, Werth E, Wirz-Justice A (2000). Functional link between distal vasodilation and sleep-onset latency? American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, 278(3), R741–R748. doi.org/10.1152/ajpregu.2000.278.3.R741
3. Okamoto-Mizuno K, Tsuzuki K, Mizuno K (2003). Effects of head cooling on human sleep stages and body temperature. International Journal of Biometeorology, 47, 98–102. doi.org/10.1007/s00484-003-0181-3
4. Hamanishi S, Eguchi E, Ito T, Nagaoka K, Ogino K (2019). Head cooling during sleep improves sleep quality in the luteal phase in female university students: a randomized crossover-controlled pilot study. PLoS ONE, 14(3), e0213706. doi.org/10.1371/journal.pone.0213706
5. Kräuchi K, Fattori E, Giordano A et al. (2018). Sleep on a high heat capacity mattress increases conductive body heat loss and slow wave sleep. Physiology & Behavior, 185, 23–30. doi.org/10.1016/j.physbeh.2017.12.014
6. Herberger S, Kräuchi K, Glos M et al. (2020). Effects of sleep on a high-heat capacity mattress on sleep stages, EEG power spectra, cardiac interbeat intervals and body temperatures in healthy middle-aged men. Sleep, 43(5), zsz271. doi.org/10.1093/sleep/zsz271
7. Reid KJ, Kräuchi K, Grimaldi D et al. (2021). Effects of manipulating body temperature on sleep in postmenopausal women. Sleep Medicine, 81, 109–115. doi.org/10.1016/j.sleep.2021.01.064
8. Herberger S, Penzel T, Fietze I et al. (2024). Enhanced conductive body heat loss during sleep increases slow-wave sleep and calms the heart. Scientific Reports, 14, 4669. doi.org/10.1038/s41598-024-53839-x
9. De Castro PF, Minko S, Vinokurov V et al. (2021). Long-term autonomic thermoregulating fabrics based on microencapsulated phase change materials. ACS Applied Energy Materials, 4(11), 11917–11924. doi.org/10.1021/acsaem.1c02170
10. Salaün F (2019). Phase change materials for textile application. In: Körlü A (ed.), Textile Industry and Environment. IntechOpen. doi.org/10.5772/intechopen.85028
11. Devan (accessed October 21, 2026). Devan® Thermic – thermoregulation technology (manufacturer information). devan.net/thermic/
12. Sleep Foundation (2026). Best cooling pillows of 2026, according to sleep experts. www.sleepfoundation.org/best-pillows/best-cooling-pillow