Light therapy is among the earliest recorded healing modalities. Solar therapy was first used by the Egyptians, and forms of light therapy were also practiced by the ancient Greeks, Chinese and Indians. There’s no question that light exerts biological effects: in fact, the body needs light to be healthy. Clinical studies are now establishing how different wavelengths of light affect the body at a cellular level, the conditions that can be successfully treated using light therapy, and the optimal conditions needed to absorb the benefits of light-based treatments. All light falls along a spectrum of wavelengths. Red and infrared light that falls within the wavelength range of 650-850 nanometers (nm) is extremely beneficial, and often referred to as the “therapeutic window”. These wavelengths of light are bioactive in humans, which mean they have a biological effect on the body like antibiotics or vitamins and affect the function of our cells. Red light emits wavelengths between 620- 700 nanometers (nm). All red light wavelengths are effective and offer health benefits, although certain wavelengths are more powerful than others–particularly those that fall between 630-680 nanometers (nm). Visible red light within this range can penetrate deep into the skin, offering rejuvenating and balancing outcomes for a range of health conditions.