Expert explains why you can never get back to sleep after waking up between 3am and 5am

There's a way to prevent this nightmare scenario

We've all been there - one second you're enjoying a lovely dream, the next your brain has decided to wake you from your slumber. You open your eyes, expecting the sun to be rising, and the day to begin.

But no. It's pitch black outside, and when you look at the time, you see it's about 4am.

And then, you can't get back to sleep. Make it make sense.

Well, one sleep expert has shed some light on just why this nightmare scenario is such a common tale for many of us.

Author and lifestyle guru Dave Asprey explained in a video to his 1.1m followers that waking up in the early hours can have a lot to do with your blood sugar levels.

Asprey said: "For most people who wake up between 3 to 5am and can't go back to sleep, it is usually [due to a] crash in your blood sugar."

He explained blood glucose levels fall, cortisol and adrenaline get released into the body, and it is these stress hormones that cause you to wake up.

"The problem is, cortisol and adrenaline wake you up. While the brain gets what it wants, you don't get your sleep," Asprey said.

There is some advice the guru had for people to try and avoid this happening though, and it might surprise you.

He recommended having a "small snack before bed," but only a very specific type of snack.

Asprey said you should have either "raw honey, collagen, MCT oil or mix all three together".

Yum.

This is because these foods all provide sustained energy, preventing blood sugar crashes.

And if your blood sugar doesn't fall, there's less chance of you being woken up during the night.