Xylitol is a natural sugar substitute that's been around since the '60s. You can find it in products like chewing gum, sweeteners—even sinus nasal sprays. But the most incredible use so far has to be its integration into the Louis Garneau Carbon Pro Team shoes.
Xylitol is derived from a number of organic sources—berries, oats, mushrooms, corn husks, sugar cane bagasse, and birch, surprisingly enough. It's a alcohol-based sugar with endothermic properties. That's why after chomping down on a piece of Xylitol-spiked gum, you get that cooling feeling—it's your saliva evaporating.
Now, Ventex, a clothing firm in South Korea, has figured out how to weave Xylitol into fabrics, allowing the same cooling sensation for your sweaty feet as it does for the interior of your mouth. The fabric—sold under the Ice-Fil brand—reacts to moisture and behaves as a refrigerant, converting it into cool air. That helps keep your feet cooler and drier during your ride. The fabric even has some UVA- and UVB- blocking abilities.