Laser hair removal works by using heat energy. This heat energy is absorbed by pigment in the hair follicles that are in an active growth phase. This heats up and thereby destroys the hair follicles, which prevents future hair growth. When this process is done multiple times, your hair is thinned out so much that it either goes away completely or becomes very fine. After the series of treatments is complete, most patients only need to return for a touch-up every 2-3 years.