What Causes Excessive Sweating?

So why does it happen? Unfortunately, science isn't entirely sure. People who suffer from it don't have more sweat glands, larger ones, or anything else in their sweat-making bits that could cause this malfunction. The current theory is that it's a genetically transferred problem in the nervous system that produces a sweat reaction when it's not actually needed. (It's known as idiopathic, indicating that we don't actually know how it happens yet.)