Neuroscience Says This Simple Sleep Habit Literally Cleans Your Brain

Often, when I’m reviewing stories about neuroscience that can help entrepreneurs train their brains to improve health and performance, there’s a moment at the end where the researchers  caution about the limits of their work.

• Sometimes, it’s a caveat walking back an extra conclusion people might be inclined to make. 
• Sometimes, it’s a wistful or wondrous note about areas in which more research should be done.
• Often, it’s a reminder not to get too far ahead of ourselves because of our old friend, “correlation versus causation.”

But very occasionally, I come across something that offers even more useful insights as we work backward, inspiring you to read previous research that shows how neuroscience suggests people might be able to improve their health.

That’s what happened recently, and it has to do with studies about quality sleep, its biological purpose, and frankly, the lack of quality sleep that many entrepreneurs and business leaders still report.

Let’s go to the research that sparked this exploration.

Writing in the peer-reviewed journal, Translational Neurodegeneration, university researchers in Australia explained that they set out to study devastating motor neuron diseases like amyotrophic lateral sclerosis (ALS), which is also known as Lou Gehrig’s disease. 

There’s no known cure for ALS, and the researchers wanted to determine whether impairment of the body’s glymphatic system, which removes waste from the brain, might be associated with onset of the disease to begin with. 

In order to understand their experiment, we first have to understand a little bit about how our bodies process protein, and how the glymphatic system works. 

As the researchers explained, our bodies rely on long chains of proteins, each made up of amino acids, which align “to perform specific tasks like creating antibodies to fight off infection, supporting cells or transporting molecules.”

When things don’t work correctly, the body can accumulate “misfolded proteins.” It’s the glymphatic system that removes this kind of waste from the brain, working mostly while we sleep.

So, the researchers’ study involved mice that had been genetically modified to express a human protein that is seen in human patients with ALS. When they fed the mice food that had been laced with an antibiotic that counteracted the human protein, they aged normally. 

But, when they fed the mice food without antibiotics, and the modified human proteins accumulated, the mice began to show “classical signs of ALS including progressive muscle impairments and brain atrophy.”

From there, they used an MRI to look at the mice’s brain structures, and they found that in the mice with the human protein unobscured, glymphatic clearance was significantly less effective than the mice who had not been genetically modified.

Other contributors to glymphatic clearance, which the study authors cites based on previous research:

• consumption of Omega-3 fatty acids, which are found in marine-based fish;
• moderate alcohol consumption (the emphasis is on “moderate;” high doses of alcohol had the opposite effect);
• exercise; and
• sleeping on your side.

It’s that last extra contributor that leaped out. Sure enough, there’s a whole body of research on mice, glymphatic clearance, and sleep that suggests that sleeping on one’s side, rather than face-down or on your back, can increase the brain-cleaning function of glymphatic clearance.

“The reasons for this are not yet fully understood,” wrote study author David Wright, “but possibly relates to the effects of gravity, compression and stretching of tissue.”

So, where does all this leave you? Certainly, I hope you never have to contend personally with motor neuron diseases. But, I also hear constantly from entrepreneurs that they’re interested in easy, science-backed life hacks that can improve their productivity and their health.

Here, it seems that a simple habit like learning to sleep on your side might offer tangible benefits. It might be even easier than you might suspect; I came across several studies suggesting a majority of people sleep on their sides automatically, anyway.

Now, maybe you’re already familiar with this earlier study, but just in case your subscription to the Journal of Neuroscience has lapsed, it’s worth revisiting.

“[L]ateral sleep position is already the most popular in human and most animals,” one of the authors of that study wrote, adding that “a distinct biological function of sleep and that is to ‘clean up’ the mess that accumulates while we are awake.”

Anyway, as I write in my free e-book Neuroscience: 13 Ways to Understand and Train Your Brain for Life, there’s nothing more fascinating than the human brain, and the unexpected ways in which it works.