Why do we rub our eyes when we're tired? © iStock

Why do we rub our eyes when we’re tired?

Maybe now you have a good excuse after an all-night Disney marathon.

Asked by: Matthew Cahill, Liverpool

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Tired eyes get dry, and rubbing stimulates the lacrimal glands to produce more fluid. Tiredness also closes your eyes, so you may rub to keep them open. Finally, there’s a connection between the muscles that move your eyes around and your heart. When these muscles are stimulated, a reflex slows the heart. This might be relaxing if you feel very tired.


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