| The human
eye reaches peak strength in the young adult, around the
mid- to late-20s. This strength involves many abilities
not measured by eye charts. Night vision, eye-hand
coordination, motion and depth perception, and color
discrimination may all improve during this time. During
the years of increasing visual abilities, nutrition is
essential for optimum vision development.
By the time we reach our mid- to late-30s, it may
begin to be difficult to focus on close objects. The
ciliary muscles that adjust the thickness of the lens
start to weaken. Meanwhile, the lens itself loses its
elasticity. Consequently, the ability of lens to focus
at close range decreases. Most people notice signs of
"aging eyes," or presbyopia, around the age of 40 to 45,
when they begin holding reading material at arms'
length. You will probably need to wear reading glasses,
bifocals, or multifocal glasses or contact lenses to
correct your vision at this stage. The condition will
usually stabilize by the age of 65 or 70 but may
progress indefinitely.
During our mid-40s, the iris muscles tend to slow.
The reflex response decreases, increasing the amount of
light entering the eye. For many people, sensitivity to
glare starts at this age. Their eyes may be overexposed
to the sun and other UV light, potentially causing
permanent damage. Eyewear with ultraviolet radiation
protection can shield the eyes from the harmful rays.
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