This “sweet spot” for sleep helps protect your brain

Whether you want to lose weight, keep your immune system firing on all cylinders, remain mentally sharp, or more… getting adequate rest is an absolute must. 

But that’s also not an invitation to sleep your life away. Because this is one instance where you can get too much of a good thing.  

In fact, a new study serves as a dire warning to anyone who may sleep way too much (or perhaps, too little).  

As it turns out, there’s a U-shaped link between sleep and cognitive decline… 

The “Goldilocks” effect strikes again 

This study featured 100 subjects, with an average age of 75 years. Most had no cognitive impairments at the study’s outset. And researchers monitored for cognitive function for roughly five years, on average.  

The subjects received yearly clinical and cognitive assessments. They also provided blood samples to be tested for APOE4, a genetic variant that raises Alzheimer’s risk; samples of cerebrospinal fluid, to look at levels of Alzheimer’s proteins; and slept with EEG monitors for a week, to measure brain activity at night. 

Unsurprisingly, the researchers found a very clear association between subjects’ sleep and cognitive decline. More specifically, subjects who slept less than 4.5 hours a night saw a significant dip in overall cognitive scores.  

But here’s what may come as a surprise: Subjects whose EEGs showed more than 6.5 hours of sleep per night saw significant declines, too.    

EEGs tend to deliver estimates that are about an hour shorter than self-reported sleep times. So these numbers equate to roughly 5.5 hours or 7.5 hours of sleep, by the average person’s alarm clock.  

And when subjects stayed within this sleep “window,” their scores remained stable—pointing to a sweet spot for sleep and brain health. Plus, this U-shaped “Goldilocks effect” remained, even after adjusting for factors like Alzheimer’s proteins and APOE4.   

Getting it “just right”   

This research appeared in a recent issue of the journal Brain. But it’s not the first study to issue a warning to short and long sleepers alike.  

Longtime readers of mine may remember when I shared the results of this study from the Centers for Disease Control and Prevention (CDC), which looked at close to 55,000 adults over the age of 45.  

Surveys showed that just about one-third of participants reported being short sleepers (clocking six hours or fewer of shut eye every night). Nearly 65 percent reported optimal sleep (at seven to nine hours nightly). And just over 4 percent were long sleepers (reporting 10 hours of sleep or more during a 24-hour period). 

As it turns out, sleep habits on either end of the spectrum were equally dangerous. 

Results revealed a bell curve of risk where obesity, mental health, heart disease, stroke, and diabetes were concerned. And subjects who slept too little or too much faced the same level of hazard in terms of chronic disease. 

So—whether you’re worried about cognitive decline or chronic disease, when it comes to sleep, it’s important to get it “just right.” And as scientific research reveals, that doesn’t necessarily mean sleeping more… but it definitely means sleeping better 

Aim for seven to nine hours of quality shuteye each night. If you need some help achieving this healthy target, you can invest in room darkening curtains or shades and start being conscious of blue light before bedtime. 

You can also turn to some safe, natural alternatives—like melatonin (I recommend starting with 3 mg and never exceeding 20 mg); L-theanine (I recommend 100 mg before bedtime); Enzyme-treated asparagus stem extract (ETAS™) (I recommend 200 mg before bed); and CBD oil (I recommend starting with a small amount and working your way up until you reach the desired result). Of course, if you ever wake up feeling groggy, that means you’re taking too much. 

Finally, for additional ways to help ward off cognitive decline, check out my Alzheimer’s Prevention and Treatment Plan. To learn more about this online learning tool, or to enroll today, click here now! 


“Hit the sleep ‘sweet spot’ to keep brain sharp: Too little and too much sleep linked to cognitive decline.” Science Daily, 10/20/2021. (