Why Do I Sleep So Hot?

And Why Wool is the Best at Helping You Keep Your Cool

Sleeping hot is a burning question on the minds of many folks shopping for mattresses and bedding. And a wool mattress or bedding can sound like a rather warm addition to what may already be some steamy nights.

While wool is a superior fiber for cold weather (those cozy sweaters, hats, and gloves), it’s also gaining popularity for warmer applications due to its performance characteristics, specifically regarding thermoregulation (keeping you warm or cool) and moisture management (dealing with sweat and water vapor).

Many mattress companies are creating technologies to address hot sleepers’ needs, usually involving chemicals, foams, gels and other doodads that are synthetic, potentially toxic, and environmentally damaging. Many of these increase exposure to electromagnetic fields (EMFs), which we are already awash in on a daily basis, and are shown to disrupt sleep and may even contribute to cancer. They’re also expensive and a useful marketing tool for companies to charge premium prices.

Here at Shepherd’s Dream, we’re completely baffled by this approach when Mother Nature has already given us perfectly good solutions to these issues, all while not creating more problems in the process. On the contrary, sleeping the way nature intended helps heal our ecosystems and support the workers and companies showing up everyday for a more sustainable future. And sleeping with all-natural bedding may just improve your sleep and your health too.

So…Why Do I Sleep So Hot?

There are many reasons someone might feel hot while sleeping. Most are perfectly normal reasons, especially when we consider that sleep is largely governed by hormones and neurotransmitters. This is why women going through menopause can begin to experience sleep disruption and body temperature issues like hot flashes.

In general, our body temperature naturally begins to fall one or two degrees toward nighttime, and it gradually begins to rise again before waking, following our cortisol cycle (learn more about that here in our Healthy Sleep Series!). But occasionally, night sweats or hot flashes can be an indicator of other health issues, so if you’re concerned, be sure to check with your doctor.

The average person sweats out 200 milliliters of water during sleep, and can lose more through just breathing, especially if you’re a snorer. This could total as much as a full cup of water, which makes us wonder…

Where does all that moisture go?

Well, a lot of it gets absorbed by your bedding, and this is where wool excels above and beyond all other bedding materials. So whether you’re a sweaty sleeper, a menopausal hot flasher, or have a kiddo that sleeps like a furnace, you’ll want to keep reading.

Wool is Breathable

Maintaining an ideal body temperature no matter the season is one of the reasons wool is so magical. It’s warm when you need it cozy and it’s cool when you need some fresh air.

The key to its success is breathability, which is defined as the ability of a fabric or material to allow perspiration and water vapor to escape through to the outside. And yet, when you want insulation, the natural crimp in the wool fibers traps little air pockets of warm air. It seems to know just what you need!

Breathability is important because if there’s no air flow, all the microscopic water droplets in the trapped vapor will condense into full on moisture, making you feel clammy and unpleasantly soaked. Sound familiar?

Synthetic fabrics, often made with petrochemicals, do not breathe well. (Think about those 70s polyester pants for reference.) Some performance fabrics get around this with the particular weave of the fabric, but the fibers themselves still promote a sweatier overall experience.

This also applies to so-called “natural” fabrics made from materials like bamboo (viscose), birch (modal), and eucalyptus (lyocell) that undergo a chemical manufacturing process that plasticizes the natural material into a substance that can be spun into fiber. Consider all the alternative compostable plastics made from corn, for example. These fabrics belong to a class of textiles called “bio-based fabrics,” and unfortunately, they’re not quite as sustainable as we’d like them to be.

Some synthetic fibers are decent at wicking moisture away from your skin (more on that next), but they are also notorious for hanging on to body odors. Anyone who has a favorite synthetic workout shirt can attest to the stench that eventually won’t go away, even with washing. This is where natural fibers outperform synthetics, not to mention the superior feel of them against the skin and their ability to biodegrade. Unfortunately, all those discarded stinky synthetic shirts will be clogging up landfills for a very long time.

Wool Handles Moisture Like No Other

Wool fibers have the ability to absorb up to 30% of its weight in water and yet somehow remain dry on the outside. How does it do this? By pulling water inward toward the core of the fiber and away from the surface, a process called wicking. In this way, wool can handle a lot of fluid before you’d ever feel it against your skin.

Anyone who adventures outdoors or works out knows that cotton isn’t the best choice for sweaty activities because it doesn’t wick well, instead growing saturated and clammy, holding all that moisture against your skin. And yet, we think organic cotton makes the best bed sheets—so what’s the solution?

A wool mattress protector prevents moisture from reaching your mattress. This is important, because not only can moisture stain the surface of the mattress, but it can build up inside the mattress and over time this can get…not so great. So we want to protect your mattress, but we also don’t want you to sleep in a puddle of sweat, which can occur if there’s a synthetic or plastic-based mattress protector on the bed. If you have one of our wool mattresses, you already know that giving it space to breathe and the occasional dose of sunlight and fresh air helps keep it in tip-top shape, so be sure to have one of our mattress protectors as well.

When we top the wool mattress protector with organic sheets, we get the best of all worlds because the protector will continue to wick moisture through the sheets and away from your skin, but you get the softness of organic cotton next to your skin. This has the added bonus of protecting the investment you made in quality sheets, helping them last longer.

What Else Can I Do to Sleep Cool?

Once you’ve got the mattress and bedding figured out, give these other ideas a try.

Lower your bedroom temperature. Experts say an average of 65 degrees Fahrenheit is an ideal bedroom temperature, so keep it between 60 to 67 depending on tolerance.
Crack a window or run a fan. Air flow is always a good thing. (Check out our blog post about indoor air quality!)
Consider your sleep attire. Just as with the fabric of our sheets, be sure to wear natural fabrics like cotton (may we suggest our Danu organic cotton sleep shirt?) and wool to bed. We love our Icebreaker wool layers, because they wick sweat, breathe and never get funky. Or go commando! There’s evidence to suggest sleeping naked carries health benefits, including increased closeness with your partner.
Create some space. Be sure to get your daily hit of bonding hormone oxytocin by cuddling with your partner, but then go to your own sleep spot on the bed so you’re not troubled by someone else’s body heat. This goes for children and furry family members as well—sorry Fido!

So What Did We Learn?

Sleeping hot is a concern for many people, and it makes sense that anyone whose sleep is disrupted by hot flashes and night sweats would look for solutions. Good news—there are natural options! We don’t need to risk our health or the health of our planet just to get a good night’s sleep. We truly believe that natural choices help us sleep better, which in turn helps us feel better, which adds up to living better.

We hope you’ve found some useful information here! If we can be of further service to you, please don’t hesitate to contact us. And be sure to follow us on Instagram and Pinterest for more healthy sleep tips.