To answer your question, the answer is in the particular wavelengths of light which are not so prevalent naturally. A specific wavelength of the blue light kills the bacteria located in most acne. The most common treatments also combine a wavelength of red light which helps to promote healing. This is how the Dermalux system works. In a recent trial, they found that 15 minutes a day over a period of 12 weeks reduced acne by 76%. Not too shabby, especially considering that they haven't discovered any ill effects to my knowledge. Best, Johnny
