Lutein is an antioxidant carotenoid that occurs in nature with zeaxanthin. Dietary lutein and zeaxanthin concentrate in the eye's macula and lens, as well as the skin, breast and cervical tissue. Both lutein and zeaxanthin protect the macula from degeneration normally associated with aging and oxidative stress. The macula is located behind the lens of the eyes, and it is responsible for focus and color differentiation. Dark green, leafy vegetables are good sources of lutein and zeaxanthin, a carotenoid closely related to lutein. While the average American intake of lutein is only 2 mg per day, other population groups consume up to 20 to 25 mg per day.
