Why Do We Blink?

What You'll Learn

• We blink to spread tears over our eyes and keep them moist
• Blinking also washes away dust and germs
• We blink about 15-20 times per minute
• Blinking gives our brain a tiny rest from looking at things
• Reflex blinks protect our eyes from fast-moving threats

Words to Know

Blink

Quick closing and opening of the eyelids

"I blinked when the wind blew."

Tear

A salty drop that keeps eyes wet and clean

"Tears washed the dust out of my eye."

Eyelid

The moving cover over the eye

"My eyelid closed when I blinked."

Cornea

The clear front window of the eye

"Light goes through the cornea."

Check What You Learned

Fun Facts

• Blinking moistens the eye by spreading tears across the cornea

  Source: American Academy of Ophthalmology

• The average person blinks 15-20 times per minute, or about 1,200 times per hour

  Source: AAO

• Tears contain proteins and electrolytes that nourish and protect the eye surface

  Source: National Eye Institute

• Blinking removes debris, dust, and microbes from the ocular surface

  Source: AAO

• Reflex blinks protect the eye from approaching objects, bright light, and irritants

  Source: Neuroscience textbooks

• Blink rate decreases during focused visual tasks such as screen use

  Source: AAO / dry eye research