When we think about sleep, most of us picture rest, maybe a few dreams, and hopefully waking up refreshed. But science is revealing that our nights are doing far more than just giving us energy for the day ahead. New research shows that while we sleep, our brains actually go into a deep cleaning mode, which is essential for long-term brain health.
Scientists have been studying what’s called the glymphatic system, a network in the brain that moves fluid around to wash away waste. During deep non-REM sleep, slow waves ripple across the brain, helping shuttle toxins out. Think of it like your brain taking out the trash while you’re dreaming of beach sunsets or cozy nights in.
Here’s where it gets interesting: studies using brain imaging suggest that sleeping on your side may help this cleaning process work better than lying on your back or stomach. The fluid that clears out waste seems to move more efficiently when we lie on our side. That’s particularly intriguing because some of the proteins that accumulate in our brains over the years are linked to memory problems and neurodegenerative diseases. Scientists emphasize that these findings are still emerging, but they point to the idea that small changes in our sleep habits — like finding the best sleep position — could have long-term benefits.
Of course, there’s no single “perfect position” that works for everyone. Sleep is personal, and comfort is key. But knowing that side-sleeping might give your brain’s cleanup crew an advantage makes it worth experimenting with.
Here’s how you can put this insight into practice for more restful sleep:
- Choose a pillow that keeps your head and neck aligned with your spine. Too high or too flat, and your muscles work overtime, which could disturb sleep.
- Even spending part of the night on your side can be beneficial. You don’t have to force yourself to stay there all night.
- Make your sleep environment cool, quiet, and comfortable. Relaxed muscles and a calm mind help the brain waves that drive this cleaning process.
While we wait for more research to fully confirm all the details, the takeaway is simple: treating your sleep with the same care you give your exercise routine or your diet matters. Even small adjustments — like considering your sleeping position — can support a clearer, healthier brain tomorrow and for years to come.
Sources of Information:
- Brain imaging studies on the glymphatic system and sleep published in journals such as Science and Frontiers in Neuroscience, 2024–2025.
- Research articles on deep non-REM sleep and brain toxin clearance from UC Berkeley and other neuroscience institutions.
