Historical Two-Segment Sleep Pattern vs. Modern Continuous Sleep

Imagine people used to sleep like this: go to bed, wake up in the middle of the night for a bit, then go back to sleep until morning.

This happened for a very long time!

It gave nights a distinct middle part where people might do things like read, pray, or talk.

But then, things changed over the last couple of hundred years.

First, we invented lights that let us stay up later.

Then, factories needed people to work on strict schedules, which meant sleeping all at once.

This, along with bright lights messing with our body clocks, made us start sleeping in one long stretch.

Now, when some people wake up in the middle of the night, they worry something is wrong, but it's actually a return to an old, natural way of sleeping.

Doctors now suggest that if you wake up, it's okay to get up for a bit and then go back to sleep.