A Natural Effect Of Aging
The eye's natural crystalline lens helps us focus on people and objects at varying distances. Unfortunately, as we grow older the human lens becomes more rigid, and without its youthful suppleness, it loses its ability to change focus, creating blurred vision at different distances. This condition - a natural consequence of aging - is called presbyopia. Most people begin experiencing the early effects of presbyopia (such as gradual loss of near vision) in their early 40's.
Clouding of the human lens
As we age, additional degenerative changes occurring to the human crystalline lens can lead to the development of cataracts. By age 65, a large percentage of us will develop a cataract, most often simply causing blurred vision. Frequent complaints of patients presenting with cataracts include difficulty reading fine print and glare driving at night.