Dr. Matt Walker

And if we selectively deprive you of just deep sleep alone, and we can do this now very cleverly, it's not as though I see you going into deep sleep and I go into your bedroom and I wake you up and then you go back to sleep, which is how we used to do it sort of 10 years ago.

Now we can use a very clever method where we play auditory tones to your brain.

but they are of a level that will not wake you up.

It's what's called a sub-awakening threshold.

And we determine that.

And by playing those tones, it forces the brain to resurface out of deep sleep.

So you will still sleep a total eight hours.

but I will have selectively excised just your deep sleep.

And when I do that, sure enough, your blood sugar ability, your ability to control your blood sugar, I should say, is impaired really quite demonstrably.

And it's for at least two reasons.

The initial thing is that your pancreas, when it sees this spike in blood sugar, it normally releases something called insulin.

And that insulin is a trigger to your body to say, start absorbing the blood sugar so we don't get this toxic, or we don't maintain this toxic spike in blood sugar.

Your pancreas, when you are under slept and specifically when you're not getting enough deep sleep does not release the appropriate amount of insulin.

Worse still, what we found is that selectively depriving you of deep sleep means that what little insulin is released,

the cells in your body become less receptive to that insulin.

So you're not releasing enough of this chemical to say, start absorbing blood sugar.

And the cells that are designed to do that, they stick a straw out into your bloodstream and they suck up the blood sugar.

They don't respond to the insulin anymore.

So on both sides of the blood sugar regulation equation, you become impaired.

And then I can give you an example upstairs in the brain.