An eyelash of a human being is a hair that grows at the edge of the eyelids. Eyelashes protect the eye from small things like dust. The average person has hundreds of eyelashes. They have a normal or typical lifespan of about 3 months.

If an ophthalmologist (medical doctor, MD) or a doctor of osteopathic medicine (DO), who specializes in eye and vision care is consulted, they believe that it is hard to track exactly how many lashes people lose each day. But they will agree "it is generally estimated that a person will normally lose 1-4 eyelashes per day". With this daily loss, it becomes easy to determine the average life lifespan of most eyelashes.

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