Diseases of the retina are the leading causes of
blindness throughout the world. Evidence points to potential benefit from nutritional and botanical interventions for the prevention and treatment of several of these conditions, including
macular degeneration,
diabetic retinopathy, retinopathy of the newborn, and
retinitis pigmentosa. Epidemiological evidence points to the potential of
antioxidant vitamins E and C,
carotenoids,
zinc, and
selenium in the prevention and possible treatment of
macular degeneration. In addition, dietary components such as red wine-high in important
flavonoids-and fruits and vegetables high in
carotenoids appear to offer some protection. While
diabetic retinopathy can best be prevented by maintaining good
blood sugar control, there are a number of nutrients and botanicals which may help prevent and treat retinopathy by inhibiting protein glycosylation, stabilizing
collagen, decreasing capillary permeability, and providing important
antioxidant effects. Extensive research on the use of
vitamin E for the prevention of
retrolental fibroplasia (retinopathy of the newborn), despite yielding promising results, has not resulted in incorporation of
vitamin E into conventional standards of care protocols.
Retinitis pigmentosa resembles the
retinal damage seen in
taurine-deficient cats. While patients with
retinitis pigmentosa do not appear to be deficient in
taurine, they appear to have faulty cellular uptake of this important
amino acid. Disturbed utilization of
vitamin A also appears to play a part in
retinitis pigmentosa, and a subgroup of patients benefit from supplementation.