Suffer a poor night’s sleep and you may find yourself nodding off during the day — you might even feel the urge to take an afternoon nap.

But if daytime napping becomes excessive, especially in the absence of night-time sleep problems, please don’t believe the myth that it’s just part of the aging process.

The fact is, the need for an afternoon nap might indicate cognitive decline or – even worse – that you’ll suffer from Alzheimer’s years down the road.

If you talk with family members of those suffering from dementia, they might tell you that bouts of frequent napping preceded some of the earliest episodes of memory loss in their loved ones.

This isn’t surprising to Alzheimer’s researchers. Many research groups studying Alzheimer’s note that even before the initial signs of memory loss, there are neuropsychiatric symptoms often related to the sleep-wake cycle.

Brain Cells Annihilated in Wakefulness Areas

One of the groups studying these phenomena is the Grinberg Lab based at the University of California, San Francisco. Their latest study was published in Alzheimer’s and Dementia in August.

They looked at the loss of brain cells and the build-up of Alzheimer’s-linked proteins in three brain regions that promote wakefulness among 13 people who died with Alzheimer’s and seven who died dementia-free.

In the Alzheimer’s group, the scientists discovered a significant build-up of tau– an overlooked Alzheimer’s causing protein– in each of the brain wakefulness regions compared to the seven people who were free of dementia. These areas of the brain overcome by tau also lost as many as three-quarters of their neurons, or brain cells.

Lead author Joseph (Jun) Oh commented:

“It’s remarkable because it’s not just a single brain nucleus that’s degenerating, but the whole wakefulness-promoting network.

“Crucially this means that the brain has no way to compensate because all of these functionally related cell types are being destroyed at the same time.”

Even more interesting, this loss of cells is ONLY found in people with Alzheimer’s.

Applies to Alzheimer’s Only

In a second part of the study, the researchers analyzed post-mortem brain samples of seven people who suffered with two rare forms of brain disease called progressive supranuclear palsy and corticobasal disease. A build-up of tau is also common to both conditions.

Researchers thought they’d find the same results, a build-up of tau equals a dramatic loss of brain cells in the wakefulness promoting areas of the brain, but guess what? They didn’t.

Compared to the Alzheimer’s tissues they’d previously studied which had a similar build-up of tau, wakefulness-promoting neurons were spared in these two rare memory disorders. Why? Researchers don’t yet know.

Dr. Oh reported that in comparison to other forms of degenerative brain disorders, “It  seems that the wakefulness-promoting network is particularly vulnerable in Alzheimer’s disease. Understanding why this is the case is something we need to follow up in future research.”

I couldn’t agree more. These remarkable findings provide a never seen before biological explanation for Alzheimer’s dementia specifically. For unknown reasons, Alzheimer’s disease uses tau to attack brain regions that keep us awake during the day. As a result, chronic sleepiness could serve as an important new early warning indicator of Alzheimer’s disease.

But that’s not all. This research reveals another important new discovery about tau and Alzheimer’s disease…

We’ve Been Looking at the Wrong Protein

For years now, Alzheimer’s researchers pointed to amyloid protein build-up in the brain as the reason for memory loss in those suffering from Alzheimer’s disease. But these new findings reveal that at least within wakefulness-promoting areas of the brain, it’s tau, not amyloid protein, that’s the main cause of memory loss.

Associate professor of neurology, lab head, and senior author of the study Lea Grinberg, MD, PhD is clear when she says:

“Our work shows definitive evidence that the brain areas promoting wakefulness degenerate due to accumulation of tau – not amyloid protein – from the very earliest stages of the disease.”

Linked to Visual and Speech Problems, Too

In another study, researchers went beyond Alzheimer’s disease. This time, they examined the brains of individuals with other types of neurological impairments. For example, the folks in this study didn’t suffer from memory loss but from loss of language and vision capability.

The results were remarkable: Post-mortem examination of the brains of individuals with language difficulties showed more tau in brain areas related to language while those with visual impairments had more tau in areas of the brain related to vision. In all cases the memory centers were less affected by tau.

The take-away from this breakthrough research is twofold: If you or a loved one is suffering from chronic daytime sleepiness, watch closely for memory lapses or signs of cognitive decline.

Also, make it a priority to prevent build-up of memory-harming proteins. For example, limit your intake of processed foods such as cheese, meat and refined grains or sugars— called “white foods” — shown to fuel memory-harming brain proteins such as tau.

Instead, enjoy a diet high in fresh fruits, leafy green vegetables, extra virgin olive oils and coconut oils. I also recommend supplementing with a good omega-3 in lieu of eating salmon or other cold-water fish that may be contaminated with environmental toxins.

Meanwhile, I’ll keep my eye on this developing area of research into Alzheimer’s disease and report back with new findings.