Human eye is an important organ of the body, it is composed of a number of highly specialized tissues which consist of distinct collagenous structures. Currently there are about twelve genetically distinct types of collagen in mammalian tissues. These types are further clubbed and are characterized biochemically into three groups – Fibrous collagens, non-fibrous collagens and filamentous collagens.
Collagen types of the eye are as in the below table:

    Fibrous              Non-FibrousFilamentous
ScleraType I, Type III  
CorneaType I, Type V Type VI
Vitreous Lens CapsuleType IIType IVType IX
Descemet’s membrane Type IVType VIII
Bowman’s membrane Type IV 
Retinal pigment epithelium Type IV 
As you get older though, your body slows down its production of collagen and Hyaluronic Acid so that your eyes, skin, ligaments and tendons, hair and nails have less and less of it. More and more research has pointed to the idea that decreasing collagen in the eyes, and/or mutations in collagen which occur with aging, can result in cataracts as well as glaucoma.

Cataracts are crystallized bits that form on the eye lens can cause obstruction of vision. Age-related cataract development is responsible for about 80% of all cataracts. Aging decreases the collagen in the eyes and is thought to be a major factor in addition to others like nutrition decline and environmental exposures.

Glaucoma is a condition of increasing pressure within the eye. Research says that weakening of the collagen structures of the eyes cause the eyeball to be supported improperly and fluids cannot drain rightly, thus causing build-up of pressure.

Like cataracts, glaucoma is another leading cause of blindness worldwide. Hence, preventing both these conditions is important to vision health as one gets older.

So how can one guard against developing cataracts and glaucoma, or help improve these conditions if they already exist? One of the best ways is to up the intake of collagen in your diet.