Deep Sleep Cleans the Brain and May Prevent Alzheimer’s

The following blog post is based on an episode of NPR’s “Short Wave” podcast, which you can listen to below.

With a new diagnosis of Alzheimer’s disease every 65 seconds, the need for research into prevention and treatment has never been more crucial. Several scientists are now looking at sleep, specifically “deep sleep”, and how it may help wash away toxins associated with Alzheimer’s disease.

What Happens in the Brain During Deep Sleep?

deep sleep prevents alzheimer's

Results published in a study from Boston University show that cerebrospinal fluid (CSF), the liquid that flows through the brain and spinal cord, can help carry away toxins in human brains. This process seems to be triggered by an initial “slow wave” of electrical activity which appears once you enter deep sleep.

During deep sleep, CSF enters the brain and exchanges with the fluid already present to wash away toxins that build up during the day. Scientists compare this process to how a dishwasher or washing machine works.

While it has been known for a while that sleep is crucial to cognitive health, the answer as to “why” was lesser known. This new research clearly shows that brain waves generated during deep sleep trigger some sort of cleaning cycle that may protect the brain against Alzheimer’s and other neurodegenerative diseases.

Could Lack of Deep Sleep be a Risk Factor for Alzheimer’s?

Have you ever felt like you cannot “think straight” when you don’t get enough sleep? Scientists are now attributing this to the buildup of toxins during waking hours, including carbon dioxide, ammonia and beta amyloid, the protein present in individuals with Alzheimer’s. As these toxins build up in the spaces between brain cells, they can disrupt neuronal activity.

Regular lack of sleep contributes to a build up of even more beta amyloid, which in turn disrupts sleep, contributing to a cycle of “bad” sleep and more beta amyloid. This can lead to an increased risk of developing Alzheimer’s disease and related cognitive impairments. In fact, losing just one night of sleep can lead to an increase in beta-amyloid protein build-up

Scientists caution that these studies are preliminary and that more research is needed to fully understand the relationship between lack of sleep and Alzheimer’s risk.

Tips for Getting a Good Night’s Sleep

  • Make sure your bedroom is dark, quiet and at a comfortable temperature
  • Try not to look at screens (phone, tv) right before bedtime
  • Go to bed and wake up at a consistent time each day to get your body into a routine 
  • Older adults should reduce long daytime naps (and nap at a consistent time)
  • Don’t consume caffeine late in the day, or eat late at night
  • Reduce alcohol intake, as this can disrupt normal sleep patterns
  • Try to relax and clear your mind in the evening (meditation can help)
  • Exercise regularly (but not right before bed)
  • Get exposure during the day to natural sunlight, as it will help calibrate your internal clock that regulates sleep – yourcircadian rhythm”