Just about every professional--myself included--has lost sleep for work at some point. But as the number of people with Alzheimer's disease has climbed, scientists have grown increasingly suspicious that sleep deprivation plays a role in the development of the condition. But how many nights can you go before the creases in your pillow spell out brain trouble?
Apparently, just one.
Sleep as nature's brain cleanser
To understand this conclusion, you first have to understand why good sleep is thought to help your brain stay healthy. In layman's terms, your brain produces waste proteins as a byproduct of regular function. These proteins naturally build up through the day. When you sleep, the flow of cerebrospinal fluid increases and flushes these proteins away.
With this in mind, scientists know that a specific kind of protein (beta-amyloid protein) can accumulate into plaques that surround nerve cells. These plaques interfere with the ability of brain cells to signal each other and are considered a hallmark of Alzheimer's.
Proof of a problem
In a study led by Ehsan Shokri-Kojori published in Proceedings of the National Academy of Sciences, researchers used a technique called positron emission tomography (PET) to measure beta-amyloid proteins in the brains of 10 men and 10 women who ranged in age from 22 to 72. The team looked at protein levels after a night of good rest and after a night of poor sleep. The results showed that beta-amyloid proteins accumulated after just one evening of deprivation, building up in areas of the brain scientists know Alzheimer's biomarkers typically appear.
The study is notable for two big reasons. First, it's the first to really confirm that sleep deprivation can influence beta-amyloid proteins in the human brain. Previous studies had observed the effect only in mice and human cerebrospinal fluid. But the study also found that the accumulation happened regardless of gender and regardless of whether the participants had a gene variant linked to Alzheimer's risk. This suggests that environmental and behavioral elements play a role in whether someone gets the disease.
Can't we just grab more sleep later to stay safe?
To be clear, researchers still have to look more closely at overall sleep patterns to figure out if the accumulations truly translate to irreversible damage. It might be that, if you normally sleep really well and can grab a few extra hours of rest here and there, you can catch up on the cleansing process and negate the health drawbacks of insufficient rest a bit. But if your sleep deprivation becomes chronic, it becomes harder and harder for you to pay back your sleep debt. Scientists know that the accumulation of beta-amyloid proteins can interfere with sleep, so the longer you go without rest, the higher your chances are that you'll create a vicious cycle that might lead to degenerative brain disease.
And therein lies the real rub. This study shows that it takes frighteningly little time for a lack of sleep to affect the brain in a negative way. Yet we live and work in a system--which we've created ourselves, by the way--based on the idea we can last much longer than science tells us. We allow the fear of being passed over or not being able to pay our bills, the desire to be known and respected, to convince us that there will be time to rest later. But then comes one more thing. One more project. One more job. For so many of us, habit and pattern mean that rest never comes. And all the while, our mental health is screaming for us to stop.
The fact is, there comes a point where wellbeing isn't just a matter of individual choice. It's a social choice. Genetics and natural aging aside, if we really want to protect ourselves from mental decline, we can't stay on this path. We have to face all our underlying psychological fears, look all of our economic and equality issues in the eye and say, together, that enough is enough. We must be courageous enough to prioritize ourselves ahead of profits, to use AI, other innovations and new processes to reconnect to a better way of living. Because as Shokri-Kojori and the 5.7 million Americans with Alzheimer's will tell you, the evidence we need change is already in front of us.