Hi there it's Matt here and welcome back to the second of this two-part

series on sleep and caffeine. In the last episode we described what caffeine is and the

different impacts that caffeine can have upon your sleep. Today we're going to

answer the question of why a cup of coffee seems to have these paradoxical health benefits, despite the damaging impact that caffeine has not really discussed yet.

But before we speak about that, there is one additional sleep consequence of caffeine that

we've not really discussed yet.

We touched upon it in the last episode, but I want to go deeper here.

And it's applicable no matter whether you are a sensitive or insensitive person to the effects of caffeine based on your genetics.

Because even if you can have a cup of coffee or several with dinner and you can

fall asleep and stay asleep, you can still suffer imperments in both the quantity

as well as the electrical quality of your deep non-rapped eye movement sleep.

And from our first episode you'll remember that stages

three and four of non-rem sleep the really deep sleep and the problem there is that you will

not be consciously aware of the loss of that electrical deep

sleep quality not unless you have as I do a sleep laboratory where you can hug yourself

up every night and observe these impacts.

But that's exactly what we've done with a number of different research studies in healthy participants.

And we've found that a cup of coffee in the evening can decrease the amount of that deep

non-rapped eye movement sleep by somewhere between 20 to 40 percent at night. And for a spot of context, I'd have to age a healthy adult by probably about 10 to 15 years to produce that kind of a reduction in deep sleep.

Or you could just choose to do it every night

by having a couple of cups of coffee after dinner

or with dinner.

...