The Joy of SweatSweating may be one of our weirdest biological functions, but it's also one of our most vital and least understood. In The Joy of Sweat, Sarah Everts delves into its role in the bodyand in human history. Why is sweat salty? Why do we sweat when stressed? Why do some people produce colourful sweat? And should you worry about Big Brother tracking the hundreds of molecules that leak out in your sweatnot just the stinky ones or alleged pheromonesbut the