Alzheimer’s Disease & Using Sleep To Help Prevent It.
When it comes to Alzheimer’s disease prevention is one of the most underutilized tools we have in our tool belt.
Symptoms of Alzheimer's disease can include;
Increased memory loss and confusion.
Inability to learn new things.
Difficulty with language and problems with reading, writing, and working with numbers.
Difficulty organizing thoughts and thinking logically.
Shortened attention span.
Problems coping with new situations
And more. All of these symptoms can be worsened by poor sleep and sleep plays a key role in our brain’s health and recovery. 1
Our body runs on a 24 hour clock, scientist call this our circadian rhythm. 2 In order for us to maximize how our body functions and how our brain functions healthy sleep is key.
When looking at the research the data shows that even 15 years before someone starts noticing the symptoms of Alzheimers disease sleep or lack thereof is leading the brain down an unhealthy path. This fact among many others show that decreased sleep function and fragmented circadian rhythms are associated with and may be a key piece of the puzzle that sets the stage for the development of Alzheimer's disease. 3
Why is it that sleep is so important? While we are still learning about the specific processes that happen during sleep it is thought that 6 key processes occur during sleep.
Brain Cells Maturing (Neural maturation)
Facilitation of learning or memory
Targeted erasure of synapses to "forget" unimportant information that might clutter the synaptic network
Thinking (Cognition)
Clearance of metabolic waste products generated by neural activity in the awake brain(a key part for Alzheimer's prevention)
Conservation of metabolic energy
These 6 key processes are thought to occur as we go through 5 different stages of sleep at night.
The Five Stages are; Wake Alert, Stage 1 or Light Sleep, Stage 2 or Deeper Sleep, Stage 3 or Slow-Wave Sleep, and Stage 4 or Rapid Eye Movement Sleep commonly known as REM sleep.
The Wake or Alert Stage is essentially us falling asleep and getting to a relaxed drowsy state. 4
The next stage is Light Sleep which amounts for around 5% of our total time asleep. During this time our muscles still have some activity and breathing is occurring at a normal regular pace. This stage last any where from 1 to 5 minutes.
We then enter Deeper Sleep or Stage 2. During Stage 2 we start to see a drop in our body's temperature and our heart rate. In the brain during this time our brain cells work powerfully and it is believed that this stage is a key part of maintaining our brains ability to grow and heal. Multiple studies have also shown that this stage plays an important role in procedural memory which includes activities like riding a bike, tying your shoes, or cooking a meal without a recipe, and declarative memory which includes memories and facts that we are able to recollect. 5 An interesting part of this stage of sleep is this is also typically when teeth grinding occurs. The Deeper Sleep Stage last for around 25 minutes during the first cycle and then typically increases with each successive sleep cycle. The Deeper Sleep Stage adds up to be around 45% of our total sleep. 6
Next is Stage 3 or the Slow-Wave Sleep Stage. Slow-Wave sleep is arguably the most important stage of sleep when discussing Alzheimer's disease and other neurological disorders. During Slow-Wave Sleep a large portion of a process called Glymphatic clearance occurs. Similar to how our muscles produce waste when they contract and are used and we then feel a fatigue or soreness brought on by the waste produced my the muscles, the brain does a similar thing. Throughout our day our brain produces waste. This waste builds up throughout the brain and cerebrospinal fluid helps to wash away the waste. However, the majority of this clearance of waste products occurs in Slow-Wave Sleep when the bulk of the process of Glymphatic clearance occurs. During this time our networks of brain cells work together to fire in a pulse like manner that helps to wash away the waste that gathers in our brain. When Slow-Wave sleep is disrupted we see an increase in the waste product beta-amyloid, a protein that is observed being increased in Alzheimer's Disease and dementia. 7 When Slow-Wave Sleep is disrupted over long periods of time Tau proteins, another waste product, start to accumulate as well. 8
Slow-Wave sleep is seen as the deepest stage of sleep and also the hardest to wake up from. If you've heard of individuals sleeping through tornado sirens, fire alarms, or other loud noises its most likely they were in the Slow-Wave Sleep stage. As a young adult we typically spend 10-25% of our sleep in the Slow-Wave stage. However, as we age the time we spend in the Slow-Wave stage decreases. There are some theories on ways to increase the time spent in Slow-Wave Sleep and we'll touch on those in a later section.
During the Slow-Wave sleep stage is also the period when our body repairs and regrows tissues, builds bone and muscles and strengthens our immune system. This stage of sleep is also the stage when sleep walking, night terrors, and bed-wetting occur. On top of that when we are woken up our of Slow-Wave sleep we will wake up feeling foggy and lethargic and our ability to think clearly can be affected for 30 minutes to an hour. Maybe the saying "You woke up on the wrong side of the bed." should be changed to "You woke up in the wrong stage." 9,10
The next stage of sleep is REM sleep, Stage 4, or the Rapid-Eye-Movement Stage. This stage isn't considered a restful stage and is typically the stage when dreaming occurs. During this stage our brain activity is similar to our brain activity when we are awake. However, at this time our skeletal muscles are completely relaxed and the only muscles that stay active are our diaphragm(which keep us breathing) and the muscles that control our eyes, this is also the stage when penile/clitoral tumescence occurs, dreaming and nightmares occur, and during this stage our breathing becomes erratic and irregular. This stage typically starts 90 minutes after we fall asleep and only occurs for a small amount of time then as we go through more of these phases we see an increase in time spent in REM sleep. 11
Those are your stages of sleep. When looking at sleep and circadian dysfunction, when Slow-Wave sleep is disrupted we see an increase in proteins that are seen in Alzheimer’s disease, specifically amyloid beta and tau proteins. Studies have shown that obstructive sleep apnea and insufficient sleep increase the risk of cognitive impairment a key part of Alzheimer’s disease. 12 Given the high prevalence of sleep and circadian dysfunction with an estimated 1 billion people in the world having sleep apnea and then up to 70% of individuals in the US not getting proper sleep at least once a month and over 30% saying they don't get sufficient sleep regularly. Sleep is one aspect of health that if we work to improve can have a profound impact on our health both short term and long term.
How do we improve our sleep?
First there are a few strategies that people typically use to help them fall asleep but in the end are counter productive when it comes to getting restful beneficial sleep.
The first alcohol. Can alcohol help you fall asleep? Absolutely. Alcohol is a nervous system depressant. Meaning it has sedative effects and can make us feel sleepy. However, as much as I enjoy a cold beer or an old fashioned, when it comes down to it alcohol is a poison. You can read more about alcohol metabolism and the effects it has on the body here. 13 . How does alcohol affect our sleep? As we learned above during sleep we have many processes that are occurring in the body and the majority of them have to do with helping our brain recover, learn, and create new circuits. On top of that our body is also recovering when we are sleeping. At the most basic level alcohol adds an additional stress to the body during one of the only times our body and brain is actively working to recover, heal, and learn. Getting a layer deeper when we ingest alcohol it is broken down into acetaldehyde and acetate. This primarily occurs in the liver but also occurs in our gut and some think in the brain as well. Acetaldehyde disrupts how the brain cells are able to work together and communicate, it also believed that similarly to how alcohol disrupts how brain cells work it also disrupts cells in the gut and will negatively affect the healthy bacteria in the gut that help to keep us healthy. While some use alcohol to get to sleep it negatively impacts the recovery processes that occur during sleep. Specifically a decrease in time spent in Slow-Wave Sleep. The most important stage for brain health and recovery. 14,15
With a higher percentage of people using marijuana than cigarettes. Marijuana is another strategy many people use to help fall asleep. However, marijuana is a brain altering drug. While there isn't yet conclusive data to show how smoking or ingesting THC leads to a direct disruption of sleep. It is thought that while THC can help individuals fall asleep faster it disrupts the amount of time spent in REM sleep. The larger issue seen with using THC as a sleep aid is the dependence some start to have when using THC regularly and the struggle to fall asleep when THC is not available. Below are two short excerpts from sleep scientist Matt Walker on the effects of THC and Alcohol on sleep.
Those are two strategies that you shouldn't use regularly to help fall asleep and without a doubt you shouldn't use alcohol chronically to help fall asleep.
Here are some strategies that can help with sleep.
If you struggle to fall asleep at night one of the first things you should look at is the environment you're sleeping in. Are you on your phone right before you go to sleep? If so your brain interprets the light on your phone similarly to the way it interprets the sun in the sky. Essentially telling your brain that it's light out, it's time to be awake, and not time to sleep. While screen time and bright lights before bed are a big contributor to our modern day sleep issues it's also one of the easiest yet hardest to stop. Many of us have made it a habit to where we fall asleep to a tv show or scroll through Instagram at night to take our mind away from work or other stressors. Habits are hard to quit. If you find yourself in the pattern of wanting to watch TV right before bed or scrolling through instagram try to switch up the activity you're doing. Instead of throwing on Netflix dim the lights and read a book, instead of scrolling through Instagram dim the lights pull out a piece of paper and journal or doodle. One of the best ways to stop a habit or form a new habit is to replace it with something as, or more enjoyable. If you're dreading reading instead of Netflix, or doodling instead of scrolling you're not very likely to change the habit long term. To replace your bright light activity find an activity that you think you'll enjoy in a less bright setting. Many people use the supplement melatonin to fall asleep, I would recommend against this and you can learn more about that here, darkness is what allows our body to naturally release melatonin to help us fall asleep. We need darkness to fall asleep.
Tip 1 for better sleep. Put down the phone. Shut the laptop.
Next is caffeine. I love coffee. I drink at least 2 cups of coffee a day and at one time I was drinking about 10+ cups a day. However, caffeine is a stimulant that's great at waking us up and keeping us awake. If you remember from earlier our body runs on a 24 hour clock and right upon waking up there are some key processes that occur to help set our brain and body up for the day. In an ideal world we would let our body wake up for about 90 minutes before we drank our first cup of coffee or other type of caffeine. More importantly though when it comes to caffeine your last cup of coffee or can of coke is going to make more of an impact on your sleep. Caffeine takes around 10-12 hours to become no longer active in the body. 16 That means that to maximize your sleep you would ideally have your last serving of caffeine 10-12 hours before going to bed. As I write this it's 1 pm, I'm drinking a cup of coffee and hoping to be in bed before 10pm. As my Grandpa Ralph used to say when teaching us how to golf, "Damnit Jacob do as I say not as I do."
Tip 2 for better sleep. Stop your caffeine intake 10-12 hours before your desired bed time.
Schedule Sleep. Your body and brain love structure. Especially when it comes to sleep. We wake up with an alarm but we don't necessarily schedule a time that we get into bed each night. Setting a sleep schedule where you are falling asleep and getting in bed at the same time every night both on weekdays and weekends can be a game-changer for sustaining a pattern of quality sleep. Putting time aside each night to wind down can also help us fall asleep faster. While many of us hope to be able to just hop into bed and fall asleep the majority of us need some time to wind-down and relax.
Tip 3. Make yourself a bedtime and evening wind down.
Keep it cool. According to sleep scientist Matt Walker when falling asleep our body needs to drop its core temperature by 2-3 degrees. To both fall asleep and stay asleep our body prefers this cooler temperature. If you're someone that struggles to fall asleep and stay asleep this is an easy way to try and improve your sleep. Put a fan on yourself or lower your AC by 2-3 degrees before bed to help you fall asleep faster.
Tip 4. Cool yourself down.
Have you ever had one of those night where you lay in bed, 20 minutes goes by and you're still just as awake as when you laid down? When this occurs its best to get up do an activity like going for a walk or reading a book then returning to bed when you start to feel tired again. Our brain is associative, meaning that if we continue to try and force ourselves to sleep when we are awake our brain will associate bed with being awake. Rather than tossing and turning and ruminating on the fact that you're struggling to fall asleep change what you're doing then return to bed when you become sleepy. This has been huge for me especially when I wake up thinking about work and am unable to fall back asleep. I'll simply get up, read about 10 pages of a book then before I know it I'm struggling to stay awake.
Tip 5. Don't ruminate on not sleeping. Change what you're doing and then return to bed when you're tired.
Last but not least, my personal favorite, Yoga Nidra. Yoga Nidra is not typically what we think of when we think of yoga. There are no positions, no stretches to hold, but rather Yoga Nidra is a conscious process of relaxation that is brought on through breathing, relaxation techniques, and visualization. Yoga Nidra is my favorite because it is backed by research and it is my go to when I am having those extremely restless nights and it seems like the brain just doesn't want to slow down. Yoga Nidra videos and audio can be found on Youtube and other apps, but my personal favorite is using Insight Meditation Timer that can be downloaded here free.
Tip 6. Bring yourself into a relaxed state with Yoga Nidra.
These are some of the most common and science backed recommendations I can make for improving your sleep. However, there are also some other sleep aids that can help that I'll briefly touch on below providing links if you want more information.
Additional Sleep Resources.
It's estimated that up to 50% of Americans are deficient in Magnesium. It is not completely known how magnesium affects the sleep cycle but we know that a lack of magnesium is going to lead to poorer quality of sleep. Magnesium can be checked by your primary care physician with a blood draw and high quality magnesium supplements can be found here. If you have healthy levels of magnesium it is unlikely supplementing with magnesium will make a difference with your sleep. To learn more about magnesium and sleep click here.
Orgasm. During orgasm the body releases the hormones oxytocin and prolactin and a decrease in the stress hormone cortisol occurs. Both prolactin and oxytocin help to promote relaxation. Prolactin is also thought to be a natural sedative. The sex hormones testosterone and estrogen are under profound regulation during sleep and sex, orgasm, and sleep are all deeply intertwined. Orgasm has also been shown to increase immune system function, decrease stress, and promote overall health. You can read more about orgasm and sleep here.
Tart Cherry Juice. I know, this is a weird one. However, there have been multiple studies that have shown that drinking tart cherry juice can help increase time asleep and quality of sleep. Tart cherry juice contains a very small amount of the presurcsor to melatonin and is high in antioxidants which helps combat inflammation. It is thought that the combination of these two are the driving factors in the improvement in sleep in individuals when consuming tart cherry juice before bed. From the studies I've read 240ml or 8oz of tart cherry juice 1-2 hours before bed can have a positive affect on sleep. You can read more about tart cherry juice and sleep here and if you really want to dive deeper into the literature you can check out another article here.
Kiwis. Similar to tart cherry juice, kiwis are one of those interesting foods that have been shown to be beneficial for sleep. Individuals that ate kiwis with the skin 2 hours before bed had better quality sleep and more time spent asleep. You can read more about kiwis and other foods that have been shown to be beneficial for sleep here and here.
I hope you found this article both beneficial and interesting and as always if you have any questions feel free to reach out to me at drcoffman@optimizecolumbus.com