The World Around Us

Chemicals in Our World

Why do we need to sleep?

Even though this sounds like a pretty straightforward question, the truth is that scientists still don’t know the whole answer! There are several theories, including the idea that sleep promotes restorative functions, that sleep promotes development and structural changes in the brain, that we sleep because it helps us to conserve energy, or simply that it may have been safer for our evolutionary predecessors to remain inactive at night. While there is evidence to support each of these (and other) theories, it remains a very difficult question to answer conclusively.


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