Excessive sweating or hyperhidrosis is a medical condition in which parts of your body release more sweat than is necessary to help control body temperature. The main areas affected are the armpits, face, hands and of course, the feet. In the feet, this can lead to damp shoes and socks which is the perfect environment for bacteria and fungus to thrive. This often results in foul smelling shoes, Athlete’s foot and thick ugly toenails.