We’ve all heard the phrase “sleep is important,” but many of us still don’t get our recommended 7 to 9 hours per night — whether it’s because of work, late-night study sessions, or binge-watching our favorite shows after finishing a long week of exams. However, recent research shows that skipping out on a full night of sleep does more than just leave you bleary-eyed and groggy the next morning. Through the buildup of toxic proteins in the brain, it could potentially accelerate the progression of Alzheimer’s disease and other types of neurodegeneration.
The brain’s nightly cleanup crew
In 2013, neuroscientist Dr. Maiken Nedergaard made a groundbreaking discovery: the glymphatic system — a specialized network in our brain that becomes especially active during sleep. It helps our central nervous system (CNS) flush out metabolic waste and excess fluid in using a network of channels and cerebrospinal fluid (CSF), ultimately draining it away to the lymphatic system. Among these waste products is amyloid-beta, a protein that is heavily implicated in the development of Alzheimer’s plaques, as stated in the National Institutes of Health.
During sleep, CSF flows more freely through the brain’s interstitial spaces to wash away debris such as amyloid-beta. This mainly occurs during the slow-wave stage 3 of non-rapid eye movement (NREM 3). In addition, the University of Rochester Medical Center found that the glymphatic system was “almost 10-fold more active during sleep and that the sleeping brain removed significantly more amyloid-beta.” Researchers also discovered that, during sleep, the cells in our brain “shrink” by 60%, allowing for CSF to clean and flush out toxins more freely in our brain tissue than when awake.
Vanderbilt’s research on sleep and brain health
At Vanderbilt, researchers are studying the connection between sleep and neurodegeneration. A Vanderbilt University study by Dr. Sepideh Shokouhi found that abnormal sleep-wake patterns were linked to an increased accumulation of amyloid-beta in the brain. This contributes to the growing research that suggests maintaining regular sleep habits in order to slow cognitive decline.
Additionally, a recent study from Vanderbilt’s Memory & Aging Project examined how poor sleep quality correlates with cognitive decline. Researchers found that older adults who reported longer sleep durations but lower-quality sleep had increased cognitive impairment. So, it’s not just the length of sleep that matters, but the quality as well.
The vicious cycle of sleep deprivation and Alzheimer’s
Because the glymphatic system is so active during deep sleep, missing out on those vital hours can disrupt its ability to remove those harmful proteins. A study from The Proceedings of the National Academy of Sciences found that losing even one night of quality sleep can increase amyloid-beta levels in the brain, telling us that chronic sleep deprivation could lead to a buildup of amyloid-beta.
Unfortunately, as amyloid-beta begins to build up, it can further disrupt sleep, setting off a vicious cycle where poor sleep accelerates Alzheimer’s progression, and the resulting brain changes further degrade sleep quality. As amyloid-beta accumulates, it may further compromise normal sleep patterns, leading to even more buildup of proteins affecting many individuals like college students, workers with long shift hours, those with insomnia, among many others.
So, what can you do?
For starters, establish a consistent sleep schedule now — yes, even on weekends if you can. Instead of staying in Vanderbilt’s Stevenson Library for those extra hours of late-night studying, consider sleeping instead. Limit the amount of caffeine intake in the late afternoon (even though Suzie’s Cafe is so close). By prioritizing sleep, you help your brain’s glymphatic system perform its nightly cleaning duties, potentially slowing or preventing the accumulation of amyloid proteins that degrade cognitive function.
Alzheimer’s might feel like a distant concern, especially for Vanderbilt students juggling exams and social activities. But investing in good sleep now could be one of the simplest and most powerful ways to keep your mind sharp in the years to come.
References
Full, K. F. (2023, December 25). Sleep health and subjective cognitive decline in the Vanderbilt Memory and Aging Project. The Journal of the Alzheimer’s Association, 19(S22). https://alz-journals.onlinelibrary.wiley.com/doi/full/10.1002/alz.080346
Ju, Y.-E. S. (2013, December 24). Sleep and Alzheimer disease pathology–a bidirectional relationship. National Library of Medicine, 10(2), 115-119. https://pubmed.ncbi.nlm.nih.gov/24366271/
McCleskey, E. (2022, January 14). Harnessing the Glymphatic System to Improve Brain Health. Houston Methodist. Retrieved February 10, 2025, from https://www.houstonmethodist.org/leading-medicine-blog/articles/2022/jan/harnessing-the-glymphatic-system-to-improve-brain-health/#:~:text=We%20spend%20one%2Dthird%20of,to%20clear%20its%20metabolic%20waste.
Michaud, M. (2013, October 17). To Sleep, Perchance to Clean. University of Rochester Medical School. Retrieved February 10, 2025, from https://www.urmc.rochester.edu/news/story/to-sleep-perchance-to-clean
National Institute on Aging. (2024, January 19). What Happens to the Brain in Alzheimer’s Disease? National Institute of Aging, National Institutes of Health. Retrieved February 10, 2025, from https://www.nia.nih.gov/health/alzheimers-causes-and-risk-factors/what-happens-brain-alzheimers-disease
Shokouhi, S. (2019). Associations of informant-based sleep reports with Alzheimer’s disease pathologies. Retrieved February 23, 2025, from https://ir.vanderbilt.edu/items/bcd8570b-bcba-4fcb-a1ca-c7909ced44ea
Shokri-Kojori, E. (2017, December 14). β-Amyloid accumulation in the human brain after one night of sleep deprivation. The Proceedings of the National Academy of Sciences, 115(17), 4483–4488. https://www.pnas.org/doi/10.1073/pnas.1721694115
