Sleep cleans your brain. And lack of sleep, we now know, causes toxins to build up.

Quartz reveals the poisonous problem with poor sleep habits:

[R]esearchers now believe wastes are forcefully pushed through the brain at a much faster and higher pace, according to Maiken Nedergaard, co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center School of Medicine and Dentistry.

Nedergaard dubbed this liquid cleaning system “the glymphatic system,” derived from the lymph system, which filters toxic waste products out of the body. The waste products that are filtered through the brain prevent neurological illnesses like Alzheimer’s and Parkinson’s.

Basically, the cerebrospinal fluid sits around your brain and spinal cord and “every six to eight hour period, filters through the brain while you’re asleep,” Tara Swart, a senior lecturer at MIT specializing in sleep and the brain, told Quartz. “The whole process takes six to eight hours.”

Much more important than your average cleaning system, this process clears neurotoxins out of your brain, specifically one called beta-amyloid, which has been found in clumps in the brains of people with Alzheimer’s disease. When this system can’t function properly due to lack of sleep, harmful remnants, like beta-amyloid, are allowed to build up.

If having enough time to sleep is a challenge for you, Swart suggests naps. Taking even 20 minutes of shut-eye is comparable to “literally plugging in your phone battery,” says Swart, similar to a power boost. For 30 minutes of downtime, your brain will experience improved learning and memory. For those fortunate enough to snag 60 to 90 minutes of rest, “new connections can form which can unleash creativity in the brain.”

(Purely anecdotal, but this is absolutely consistent with how I feel most mornings. Hung over, like there’s some kind of chemical interference inside my system. This research is absolutely consistent with my sensations.)