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Human BodySurprise 4/5Difficulty 3/5Reviewed on September 14, 2026

There is a reflex that makes you sneeze when you look at the sun.

Why it is true

The photic sneeze reflex affects about 18 to 35 percent of people. When sunlight suddenly enters the eyes, the optic nerve stimulates the trigeminal nerve, which triggers the sneeze. It is an inherited trait.

Source: Nature

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