The Dalai Lama says sleep is the best meditation. That’s probably because sleep is also the best tool for cleansing the brain of neurotoxins.

According to the National Sleep Foundation (NSF) 40 million Americans suffer from sleep disorders. Lack of quality sleep raises the risk for a slew of serious health issues including neurological disorders.  There’s a growing body of evidence that links sleep disorders to an increased risk for Alzheimer’s, depression, cancer, memory problems and other neurological diseases. One underlying reason is revealed in recent studies that have found that toxic molecules involved in neurodegenerative disorders accumulate in the space between brain cells during our waking hours.

Researchers from the National Institute of Neurological Disorders and Stroke (NINDS) discovered that the brain cleanses itself of these toxic molecules during sleep. The hypothesis is that during sleep a “plumbing system” called the glymphatic system may open, letting cerebrospinal fluid (CSF) (a clear liquid surrounding the brain and spinal cord) flush veins throughout the brain. Waste (toxic molecules) gets dumped into the CSF and transferred into the blood where it’s processed out of the brain. It’s only during sleep that there’s an increase in brain fluid flow and the space between cells get a power cleaning.

In this study, NINDS researchers tested whether the glymphatic system controls brain fluid by injecting mice with a toxic protein associated with Alzheimer’s disease called

amyloid beta (β-amyloid). Amyloid beta (β-amyloid) is a waste we all produce. They measured how long it lasted in their brains when the mice were asleep and when they were awake. The toxin disappeared faster in mice brains when the mice were asleep. In other words, metabolic waste of neural activity was cleared out of the sleeping brain at a faster rate than during the awake state.

Space between the cells is where brain toxins can accumulate. The space between brain cells changed a lot between conscious and unconscious states. An article in Science reported that when CSF is cleaning out the brain there is a 60% increase in the space between cells.

In a TED talk in San Francisco, California, neuroscientist Jeff Iliff explained that the brain doesn’t have the room to accommodate the lymphatic system used to clean the rest of the body. The CSF is the “Mr. Clean” that sweeps through the veins, between cells sweeping off neurotoxins. Iliff also highlighted the hypothesis that neurological disorders and mental health problems might be linked to an accumulation of neurotoxins between brain cells.

We know that maintaining a healthy brain means getting enough sleep. When we don’t sleep, our brains can’t clean themselves. It’s no surprise that many sleep disorders are now linked to chronic pain, diabetes, cancer and neurological diseases, like Alzheimer’s. Consult a functional medicine doctor if you have sleeping problems. Sweet dreams are made of clear and clean brains.