Carotenoids
Are a family of antioxidants that give fruits and vegetables their red or yellow color. The dominant pigments in the macular portion of the retina are lutein and zeaxanthin. These yellow pigments filter out visible blue light which, can cause oxidative damage to the retina.
° ATP
° Cornea
° Drusen
° Iris
° Lens ° Macula
° Optic Nerve
° Pupil
° Retina
° Sclera
Lutein and Zeaxanthin
Are the only carotenoid antioxidants found in the eye.
Antioxidants
Antioxidants are nutrients that stop dangerous free radical (oxidative) damage and degeneration to healthy cells that occur when the numbers of positive and negative electrons in a molecule do not exactly balance. Sometimes initiated by normal metabolic processes within the cell and photochemical damage from ultraviolet and high-energy visible blue light, this activity initiates a chain reaction of electron "stealing" resulting in multiple cell degeneration.
Conditions in the outer retina are optimal for these effects because of the high concentrations of polyunsaturated fatty acids in the photoreceptor outer segment membranes. The resulting damage, including incompletely degraded molecules and impaired function of the retinal pigment epithelium, could lead to macular degeneration.
Lutein acts as an antioxidant in the eye and it is the most effective carotenoid to prevent these fat compounds from losing their electrons and oxidizing in the human serum and the eye. Lutein can help protect the macula against this damage and also maintain the normal function of blood vessels that supply the macular region.
In the blood, lutein is 10 times more active as an antioxidant than Vitamin E and helps diminish the harmful effects of LDL cholesterol. In a 1995 study, it was shown to increase respiration and lower the incidence of lung cancer by 75%.
