The LED light therapy is a painless, relaxing skincare treatment that plumps up aging skin by boosting collagen production and treats acne by killing bacteria. LED stands for light-emitting-diodes. First developed by NASA, LED works by sending energy-producing packets of light into the deeper layers of the skin. light therapy treats various skin conditions and concerns, such as acne, fine lines and psoriasis. It comes in different types, including red light LED therapy and blue light LED therapy, which are sometimes used in combination.