Age-related macular degeneration (ARMD) is a degenerative condition of the macula (the central retina). It is the most common cause of vision loss in Americans age 50 and older, particularly in blue-eyed, post-menopausal females. Its prevalence increases with age.
AMD is caused by arterial damage, which decreases blood flow into the capillaries that nourish the retina and macula and deprives the sensitive retinal tissue of oxygen and nutrients it needs to function and thrive. As a result the central vision deteriorates.
The macula is located at the center of the retina. The retina sends light from the eye to the brain, and the macula allows you to see fine detail.
Macular degeneration varies widely in severity. In the worst cases, ARMD causes a complete loss of central vision, making reading or driving impossible. For others, it may cause only slight distortion. Fortunately, macular degeneration does not cause total blindness since it does not affect the peripheral vision.
Macular degeneration is classified as either wet (neovascular) or dry (non-neovascular). About 10% of people who suffer from macular degeneration have wet AMD. This type occurs when new vessels form to improve the blood supply to oxygen-deprived retinal tissue. However, the new vessels are very delicate and break easily, causing bleeding and damage to surrounding tissue.
People with wet macular degeneration develop new blood vessels under the retina. This causes hemorrhage, swelling, and scar tissue. The more common form of AMD, dry macular degeneration, results in less severe, more gradual loss of vision.
Macular degeneration may be caused by a variety of factors. Genetics, age, nutrition, smoking and sunlight exposure all play a role.
Several peer-reviewed studies have shown a strong link between nutrition and the development of macular degeneration. It has been scientifically demonstrated that people with diets high in fruits and vegetables (especially dark green leafy vegetables and berries) have a lower incidence of macular degeneration. The almost seven year Age Related Eye Disease (ARED) study conducted by The National Eye Institute demonstrated a 25% decrease in the progression of diagnosed macular degeneration in those people who supplemented their diets with specific minerals and antioxidants.