Thermoregulation is a term applied to describe the mechanism used by mammals to control their own body temperature. The ability to stay "Cool in the warm, warm in the Cool" is an essential survival skill. 

Over the millennia, fabrics,weaves, andmoisture wicking have all come under investigation in the name of thermoregulation. Nowadays there are evenSmart Fabrics containing low temperature Phase Change Materials (PCM) or micro-encapsulated phase change materials (Micro PCMs) or even block copolymer products... But like many modern advances PCMs can seem over-complicated, especially when a typicalcotton Jersey-weave T-Shirt has consistently been called the number one contender in the thermoregulating undergarment department. But as always, rotten-cotton has been called a lot of things ahead of humble Hemp T-Shirt. 

So what makes Hemp so cool in the warm and warm in the cool? Scientists Khan, Warner and Wang implore us to look at how the plant itself behaves. Hemp is lightweight, with a hardy character, protective and reflective against sun and cold alike. Such characteristics are demonstrated in the ease  with which the ‘weed’ grows, faring as well against a frost, as a drought, as a strong wind. These strengths carry over into the textile it creates -a thermoregulating and lightweight fabric that’s breathable in the heat (perfect for the desert, the beach, or a hot run), and insulating in the cold (Ideal for the first layer on a snow day).

Not only that, Hemp is also  UV-Protective. Elvis (also warm in the cool and cool in the warm) said: “Truth is like the sun. You can shut it out for a time, but it ain't going away.” The sun is powerful,  andthe science around UV protective clothes is vast. Tests so far into fabric have mostly taken into account three factors; the weave, the die and the weight (tightly woven, darkly died, and heavy - being the optimum protectors). When it comes to Hemp in its most basic, middleweight, unbleached form, Wama underwear conducted an SGS test  in 2019, showing a 99% protection rate against UV-A and UV-B rays (UPF 50+) - which kicks cotton to curb, and even gives silk a run for its money.