Lack of Sleep is Tied to Cognitive Decline

March 11, 2019

ReferencesSleepSleep ReviewAlzheimer's DementiaSleep MedicineNational Sleep FoundationOxid Med Cell LongScience NewsIOS Press,

This is distressing. All of us have some issues with sleep. It might be the most common thing folks complain about to me in my practice. We rattle off the usual list of good sleep practices, (aka: Sleep Hygiene) like don't nap too long in the day, get exercise, turn the lights down earlier in the evening, don't eat a lot before bed, go to bed hungry, turn off lights in your bedroom, keep a schedule. All that, especially this weekend when we lose an hour of sleep. 

But what is sleep's function? Let's get to the heart of this issue. Sleep isn't consolidating memory and making dreams that predict your future, like history has suggested it does. Sleep is all about rinsing and flushing your brain. Your glymphatic system in your brain goes into action when you sleep, with a doubling or tripling of flow, thinking your brain by as much as 15%. You are flushing out gunk. All those neurotransmitter breakdown products get flushed. But I believe it's more fundamental than that.

We now know that copper and iron play a role in our brains. They are unique toxins and have to be removed by a protein called APP, amyloid precursor protein. Each time a molecule of copper, or iron, is excreted out of our brains, a tiny piece of the APP protein breaks off and is also excreted into the interstitial space (between cells). It's amyloid accumulating in our brains that makes for Alzheimer's. As we sleep, it's amyloid that we need to wash out. The longer we sleep, and the better quality of our sleep, the more we flush. Get it? Would it make sense to you that men, who never give any iron away, and who havehigher body iron burdens get Alzheimer's sooner than women? 

With that background, we come to these studies that link lousy sleep to cognitive decline. Do I need to argue the point at all? It makes perfect sense. If you can't sleep, you can't flush out iron. Men have much more iron than women because they never had babies or periods. And then, it should be no surprise that men get Alzheimer's 10 years before women.

It starts early. Lousy sleep in your mid-life predicts cognitive decline later.

Now here is where I'm fascinated. MicroRNAs. Tiny bits of messenger RNA that is floating around in your body. They function as hormones by themselves, or as the basis for making small peptides. We now have studies that show you can examine the mRNA in your blood and demonstrate your sleep, dementia risk ratio. There are patterns of mRNA that are associated with lower cognition, and with lower sleep. The door that opens is that of peptides. Can we find peptides that we can manufacture and give to you to help your sleep? And would that help your cognition? I'm going to get to that in a couple of months. Hang in there. This is a very interesting journey. Meanwhile, go take a small nap to make up for daylight savings.

WWW: What Will Work for me. I got all my clocks changed this weekend. And I spent the weekend reading about peptides and sleep. I'm trying to focus on all the standard sleep "hygiene" strategies to get to sleep and stay there. If I get 10k of walking in, I sleep much better. If I can resist too big a supper I sleep better. So, there is some truth for me to all those strategies. I'm already older so cognitive decline is worrisome. I have given away blood 4 times now to get my ferritin down.

Pop Quiz

  1. What is the purpose of sleep? Answer: It's your brain on flush. Getting rid of gunk.
  2. What is the principle "gunk" of Alzheimer's? Answer: a small protein fragment called beta-amyloid. It accumulates in plaques.
  3. Where does beta-amyloid come from? Answer: exporting toxic minerals out of your brain.
  4. A good night's sleep flushes out amyloid, and reduces your risk of cognitive decline. T or F. Answer: Bingo. True.
  5. Cognitive decline can be predicted by your risk of lousy sleep way early in life. T or F. Answer: Also true. Conclusion - you've got time. Make a habit of getting a good night's sleep.