Photo by Tonia Kraakman
I’m sure you're wondering, why are we talking about wool in the middle of July? Isn’t this topic better suited to winter? Well, as I write this, it’s 82 degrees Fahrenheit (28 Celsius) and I’m wearing a knitted merino wool tank top. Yes, even in a heat wave, you’ll find me wearing wool. Why? Because wool isn’t just for coats and cozy sweaters. This miracle fiber has loads of remarkable properties that make it naturally suitable for all seasons and many situations. Wool certainly does keep you warm in winter, but did you know it can keep you cool in summer? It can also wick moisture away from your body and prevent odors from clinging to your clothes. It has been shown to improve sleep quality in a range of temperatures as well. Despite its warm and cozy reputation, wool is the best fiber for a myriad of warm-weather applications.
We know that wool’s natural insulating properties help regulate body temperature—this is what keeps you warm in the winter, but it also means wool can also help keep you cool in the summer. It’s incredibly breathable, unlike synthetic fibers, and it can absorb up to 35% of its weight in moisture without feeling wet. That means that when you sweat, a wool garment can absorb that moisture and hold it away from your body instead of trapping it next to your skin, thus reducing the humidity and making you feel cooler. And unlike cotton, which loses its insulating ability when wet and stops wicking moisture, wool continues to insulate even as you sweat. This is the story behind the popular outdoor enthusiast phrase, “cotton kills”. Wool garments create a microclimate around your body that adapts easily to changes in the environment to keep you comfortable, no matter the temperature.
Curling up to doze under a wool blanket seems like a perfect way to spend a winter afternoon, and it is! But wool can help your sleep health year round. That magical temperature-regulating feature of the fiber means that wool sheets and pajamas can help keep you at an ideal temperature throughout the night. As already mentioned, wool absorbs sweat better than cotton or synthetic fibers, so no more walking up drenched in the middle of a hot summer night. Wool can move moisture twice as well as cotton and ten times as well as polyester. As your skin produces moisture during sleep, wool fabric absorbs that moisture and lowers the relative humidity of the area around your body. It similarly releases moisture back into the environment when the humidity decreases, keeping the change in humidity much lower than cotton or polyester sheets can. This effect of wool bedding has been shown to help people stay asleep longer and wake less frequently through the night.
Another study showed that sleeping on top of a wool blanket or sheets can reduce the time it takes to fall asleep to just over ten minutes, compared to about 25 minutes for polyester and nearly 30 minutes for cotton. I don’t know about you, but I could all the help I can get when it comes to getting a good night’s sleep. Falling asleep quickly and staying asleep longer sounds like a dream. Time to get new sheets!
Wool is remarkably odor resistant—and when it’s hot enough to sweat through your shirt without even lifting a finger, that is a truly valuable quality! Because it so good at absorbing water vapor and wicks moisture away from your skin, it reduces body odor from sweating. Wool fibers trap odor-producing compounds and prevent them from releasing, so the fabric itself doesn’t give off a bad smell. While I have to throw my cotton tanks and tees in the wash after only a few hours of wear in the summer, I can wear a wool garment several times before it requires laundering. Not only does this save water and electricity, it saves me time and energy with less frequent laundry days!
So wool is not just for wrapping yourself up in the winter. Next time you go for a summer hike or need to replace your sheets, consider going for wool fabrics instead of cotton or synthetics. Your body (and your friends within smelling distance) wool thank you.
Data from the International Wool Textile Organisation.