Our vision is a precious gift that can easily be taken for granted. Below are a few excellent natural products that have often been used to support eye health:
Lutein & Zeaxanthin
Lutein is a carotenoid that is typically found in combination with its stereoisomer, zeaxanthin. Lutein and zeaxanthin are the two major carotenoid pigments in the human macula and retina. They are thought to function as antioxidants and as blue light filters, protecting underlying ocular tissues from photodamage. Lutein and zeaxanthin are found in high levels in foods such as green vegetables, egg yolk, kiwi fruit, grapes, orange juice, zucchini, squash, pistachio nuts, and corn. Foods containing high concentrations of lutein are associated with the greatest eye health benefits. Epidemiological evidence has associated high dietary lutein intake with a reduced risk of developing age-related macular degeneration (AMD) and cataracts. Increasing dietary lutein intake increases serum lutein levels and macular pigment optical density (MPOD). There has been some speculation that patients with AMD might malabsorb lutein. However, lutein increases serum levels and macular pigment optical density similarly in both healthy controls and patients with AMD.
Vitamin A is necessary for the maintenance of the epithelium of the conjunctiva and cornea. It’s also necessary for epithelial RNA synthesis. In the retina, retinol is converted to cis-retinal, which combines with opsin to form rhodopsin, the visual pigment. Retinal is required by the eye for the transduction of light into the neural signals that produce vision. The most specific indicator of vitamin A deficiency is xerophthalmia, which is initially manifested by night blindness that progresses to complete visual loss if untreated.