Eye nutrients lutein and zeaxanthin are a class of carotenoids that help protect vision and prevent cellular damage. These are one of the two subcategories of carotenoids, the other being carotenes. While carotenes are orange pigments, lutein and zeaxanthin are yellow pigments. This class of molecules is termed xanthophylls.
Cataracts and age-related macular degeneration (AMD) are some leading causes of visual impairment and blindness. Eye nutrients lutein and zeaxanthin carotenoids are antioxidants located in the macula (retina) part of the eye (Landrum et al., 2001). Their deficiency can lead to visual impairment.
Lutein and zeaxanthin are not produced in the body and must be obtained from food. These carotenoids help filter harmful high-energy blue wavelengths of light. This helps protect and maintain healthy cells in the eyes. Intake of this class of compounds helps prevent cataracts and AMD (Krinsky et al., 2003).
Eye nutrients lutein and zeaxanthin come from compounds that give yellow, orange, and red colors to plants and animals. There are two types of carotenoids: carotenes and xanthophylls. Bacteria, fungi, algae, and green plants synthesize the pigments. We can see them most conspicuously in flowers, pollen, and fruit like carrots, tomatoes, citrus fruits, sweet potatoes, and apples.
The body does not synthesize carotenoids. We obtain these from foods or dietary supplements.
Carotenoids help trap solar energy and make it available for plant growth. They are part of chlorophyll. Carotenoids are responsible for the biological coloration of animals. This class of molecules is bleached by light on exposure to atmospheric oxygen. Carotenoids are insoluble in water; these dissolve in fat solvents like alcohol, ether, and chloroform.
Carotenoids are found in orange, yellow, and red fruits and vegetables like pumpkin, carrots, tomatoes, livers of animals, and egg yolk. They assist normal metabolism and growth.
Carotenoids are an essential component of the human diet. They act as antioxidants within the body, protecting it against cell damage. The common carotenoids are beta-carotene, alpha-carotene, lutein, zeaxanthin, lycopene, and astaxanthin.
For beta carotene, carrots and pumpkins are ideally followed by spinach, sweet potatoes, cantaloupe, and dandelion greens. Tomatoes, watermelon, and grapefruit are the best sources of lycopene. Dark green leafy vegetables such as spinach and kale are rich in lutein and zeaxanthin.
Green leafy vegetables are the richest sources of these carotenoids. These have 15-47% lutein but a shallow (0.3%) zeaxanthin content. Fruits and vegetables of various colors should be consumed to increase carotenoid dietary intake (Sommerburg et al., 1998). Corn and corn products were also rich in dietary zeaxanthin (Perry et al., 2009).
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