Question:
What is Zeaxanthin?
Answer:
Zeaxanthin belongs to a class of antioxidant compounds called carotenoids. In the eye, lutein is the predominant carotenoid (located in the periphery of the macula), while the concentration of zeaxanthin is greatest in the center, where conditions most favor the formation of free radicals.
 
Both lutein and zeaxanthin are important in maintaining eye health. In their capacity as pigments, these compounds help screen out high-energy light, protecting underlying tissues from photo-induced damage. They also act as antioxidants, helping to protect the macula from damage due to oxidative stress. Both functions can help reduce the risk of age-related eye disease.
 
Lutein and zeaxanthin are found together in many food sources. Dark green leafy vegetables (such as spinach) are the primary source. Lesser amounts are available in other colorful fruits and vegetables, including broccoli, orange peppers, corn, peas, persimmons, and tangerines.
 
References:
  1. Handelman GJ. Carotenoids as scavengers of active oxygen species. In: Cadenas E and Packer L, editors. Handbook of Antioxidants. New York:Marcel Dekker Inc 1996; p 259-314.
  2. Hankinson SE et al. A prospective study of nutrient intake and cataract in women. Brit Med J 1992;305:335-339.
  3. Yeum KJ et al. Measurement of carotenoids, retinoids, and tocopherols in human lenses. Invest Ophthalmol Vis Sci 1995;36: 2756-2761.
  4. The Eye Disease Case-Control Study Group. Risk factors for neovascular age-related macular degeneration. Arch Ophthalmol 1992;110:1701-1708.
  5. The Eye Disease Case-Control Study Group. Antioxidant status and neovascular age-related macular degeneration. Arch Ophthalmol 1993;111:104-109.
  6. Seddon JM et al. Dietary carotenoids, Vitamins A, C., and E, and advanced age-related macular degeneration. J Am Med Assoc 1994;272:1413-1420
  7. Landrum, J.T., et al. Analysis of zeaxanthin distribution within individual human retinas. Meth. Enzymol. 1999; 299: 457-67.