Have you ever wondered why people say, Cotton Kills?
Clothing keeps you warm by trapping warm air near your skin. That’s how cotton kills. When cotton gets wet, it ceases to insulate you because all of the air pockets in the fabric fill up with water. When you hike, you perspire, and any cotton clothing touching your skin will absorb your sweat like a sponge.
If the air is colder than your body temperature , you’ll feel cold because your cotton clothing is saturated and no longer providing any insulation. This can lead to disorientation, hypothermia, and potentially death if you become too chilled. Remember, hypothermia can occur in temperatures well above freezing and become serious if you get wet and chilled.
Wet cotton does not wick water away from your skin. Cotton garments can absorb up to 27 times their weight in water, something which means they take forever to dry out and actively work to cool your body in even moderate temperatures.
Wicking fabrics move water from wet areas to dry ones using a process called capillary action. A wicking baselayer shirt will move moisture from the surface of your skin to the outer layers of your shirt leaving the part of the fabric touching your skin dry. This is why layering is such an effective clothing strategy for hiking because wicking fabrics move water away from your skin and up through your layers one after another, enabling the fabric near your skin to trap insulating air and retain your body’s warmth.
The saying ‘cotton kills’ suggests that cotton is not an ideal clothing material for when the temperatures are low. This is because cotton:
- Has poor insulation
- Is a poor wicking fabric
- Has a long drying time
- Is a heavy fabric
Although appreciated for being durable, non-itchy, and soft, cotton is not an ideal material for hikers, especially in cold weather. Your hiking clothing should be moisture-wicking, odor-resistant, and quick-drying. Cotton lacks most of these qualities. Combining cotton and hiking in cold weather could make ‘cotton kills’ a reality for you through risk of hypothermia.
Avoid wearing garments that are labelled as corduroy, denim, flannel too as these are all made with cotton. In addition, steer clear of cotton-polyester blends, for example 50/50. They still might kill you in cold weather, it may just take a little longer.