Red light therapy works by acting on the body’s cells called mitochondria. With more energy, other cells can work more efficiently, doing things like repairing skin, boosting new cell growth and enhancing skin rejuvenation. More specifically, certain cells absorb light wavelengths and are stimulated to work. Red light therapy has been shown to: Stimulate collagen production, which gives skin its structure, strength and elasticity. Increase fibroblast production, which makes collagen. Collagen is a component of connective tissue that builds skin. Increase blood circulation to the tissue. Reduce inflammation in cells.