Macular degeneration
Macular degeneration is an incurable eye disease and is the leading cause of blindness for those aged 55 and older in the United States, affecting more than 10 million Americans, out of a population of 310 millions.
Macular degeneration is caused by the deterioration of the central portion of the retina, the inside back layer of the eye that records the images we see and sends them via the optic nerve from the eye to the brain. The retina's central portion, known as the macula, is responsible for focusing central vision in the eye, and it controls our ability to read, drive a car, recognize faces or colors, and see objects in fine detail.
As we age, their chances for developing eye diseases increase dramatically. Unfortunately, the specific factors that cause macular degeneration are not conclusively known and research into this little-understood disease is limited by insufficient funding.
The American Macular Degeneration Foundation, AMDF Web site will help you to better understand macular degeneration. To understand macular degeneration, you should have a basic knowledge of the anatomy of a normal human eye.
For an animation showing the loss of central vision from macular degeneration, click here. (This video presentation requires Quicktime.)
Lutein and zeaxanthin
The yellow color of the macula lutea is due to the presence of the carotenoid pigments lutein and zeaxanthin. In contrast to human blood and tissues, no other major carotenoids including Beta-carotene or lycopene are found in this tissue. The macular carotenoids are suggested to play a role in the protection of the retina against light-induced damage.
Epidemiological studies provide some evidence that an increased consumption of lutein and zeaxanthin with the diet is associated with a lowered risk for age-related macular degeneration, a disease with increasing incidence in the elderly1.
Lutein and zeaxanthin act in two ways protecting ocular tissue: first as filters for damaging blue light, and second as antioxidants quenching excited triplet state molecules or singlet molecular oxygen and scavenge further reactive oxygen species like lipid peroxides or the superoxide radical anion.
Food sources of lutein and zeaxanthin include eggs, kai lan, spinach, turnip greens, collard greens, romaine lettuce, broccoli, zucchini, corn, garden peas and Brussels sprouts. To maximize the availability of the carotenoids in the foods listed above, the foods should be eaten raw or steamed lightly.
OCCUsharp by Live-well contains lutein and zeaxanthin derived from Marigold Flower. It comes with a VERY SPECIAL “Buy 2 Free 1+1” offer.
Vitalux Plus by Novartis delivers 4mg lutein with beta-carotene, Vit C, Vit E, Vit B2, selenium, zinc and copper in a Time-Release tablet.
Journal Reference:
1. Stahl W. Macular carotenoids: lutein and zeaxanthin. Developments in Ophthalmology. 2005;38:70-88.
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