The primary function of the lens of the eye is to collect and focus light on the retina.
The lens separates the aqueous from the vitreous humors and is composed of epithelial cells that produce the protein of the lens, crystalline.
The lens refracts the rays of light and brings it to a focus on the retina.
The retina contains the rods and cones required for proper vision. In order for normal vision to occur, light must interact with rods and cones to create a nerve impulse. The impulse is then transmitted to the visual center in the brain for interpretation.
The eye depends upon a rich supply of nutrients and oxygen. These are provided by an enormous flow of blood that travels through it. The solid mass of the lens is 98% protein. Because these proteins undergo the chronic stresses of light and oxygen, they become damaged with time. As new cells are formed, the aged cells become compressed into the center of the lens. Proteins collect and dehydrate around this site and the flexibility of the lens thus becomes compromised.
These dehydrated proteins become oxidized and damaged, forming age-related cataracts.
Cataracts are another chronic disease that can be prevented.
In young lenses, damaged proteins are minimal and the defenses that directly protect the lens against the initial oxidative assault are more than adequate.
The molecular antioxidant vitamins C and E, the carotenoids (lutein, beta carotene), along with the antioxidant enzyme system of superoxide dismutase and the glutathione redux cycle, are the primary agents responsible for this protection.Secondarily, proteolytic enzymes selectively remove the damaged proteins that underwent oxidation.
Accumulation of photo-oxidized proteins indicates that the protective systems described are not keeping pace with the damage done to lens proteins. The Athlete’s Diet recommends athletes take a combination of antioxidant nutrients early in life to prevent cataracts from developing later in life. Antioxidants work best synergistically as a group. Vitamins C, E and beta-carotene form an alliance to protect the eye from free radical attack.
Vitamin C is the most effective, least toxic, water-soluble antioxidant in nature. The concentration of vitamin C in the lens is five times higher than in other tissue sites. With age, these lens concentrations fall, which may account for the increased amount of oxidized proteins found with aging.
Vitamin E is a lipid-soluble antioxidant that inhibits lipid peroxidation and stabilizes lens cell membranes. Vitamin E activity is enhanced by vitamin C. Vitamin C also enhances glutathione recycling.
The macula is the portion of the eye responsible for fine vision. Age related macula degeneration (AMD) is the primary cause of incurable blindness and severe visual loss. Over a quarter of athletes 65 years or over have signs of macular degeneration.
Low intake of antioxidant vitamins and minerals is theorized to cause AMD.
The biological plausibility of preventing this is focused on controling the oxidative by-products by intercepting and quenching free radicals before they can generate an autoimmune or inflammatory response. The autoimmune response generated against oxidized LDL is believed to be the driving force behind macular degeneration.
LDL, the loser form of cholesterol, is damaged by blue wave free radicals causing the loss of cell fuction (vision). Higher levels of vitamin C, vitamin E, and beta-carotenes, along with bilberry anthocyanosides, lutein and lycopene are protective against the damaging effects of excessive light exposure on the macula and retina.