Lutein is a carotenoid, meaning a natural colorant or pigment, found in dark green leafy vegetables such as spinach, plus various fruits and corn. Egg yolks are also sources of lutein.
Lutein provides nutritional support to our eyes and skin the only organs of the body directly exposed to the outside environment. Lutein has been linked to promoting healthy eyes through reducing the risk of macular degeneration. Other studies suggest that a mixture of nutrients, including lutein, may provide supplemental antioxidant capacity to the skin, helping counteract free radical damage.
Lutein also filters the high-energy, blue wavelengths of light from the visible-light spectrum by as much as 90%. Blue light, in both indoor lighting and sunlight, is believed to induce oxidative stress and possible free-radical damage in human organs exposed to light, such as the eyes and skin. Blue light is not the same as the commonly known ultraviolet A and ultraviolet B wavelengths of the invisible spectrum.