LED (light emitting diode) Therapy is your answer to almost all problems with hair loss. Two wavelengths, red and yellow, are used to increase the strength of your hair as well as to stimulate hair growth. Red light stimulates the circulation of blood as well as metabolism in the area it is positioned. Yellow light stimulates the production of collagen, which is vital to firming the scalp. Both therapies take 20-minutes and it is recommended that they be performed in conjunction with each other so that the benefits can be seen distinctively.