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Why Sleep Is the Best Protection for Health, Memory, and Mood

Sleep tips for overcoming diseases, memory problems and mood disorders.

Sleep deprivation is dangerous. While I have heard that before and have even worked with clients through the years on strategies to help them improve their sleep, I have been guilty of falsely believing my own decreased sleep was normal and even somewhat noble. As a mother, I went without sleep to tend to my child in her first year of feedings which was subsequently followed by years of decreased sleep to get work done while she slept. Yet this culturally reinforced work-over-sleep mentality has now been shown to be more dangerous than many other negative health habits, which makes sense when realizing that sleeping is the body’s time to repair, heal, and assimilate learning and long-term memory. In other words, it’s not just for beauty, although that smooth skin glow is a nice free benefit.

Matt Walker gives a powerful TedTalk that challenges norms about sleep, citing sleep deprivation as a public health crisis and urging sleep as the first line of defense against disease and mental illness. Limited sleep impairs memory, attention, and cellular repair, and increases inflammation, and stress response, and has been implicated in shortened lifespans and diseases like cancer and Alzheimer’s Disease. Because sleep is regulated by the body’s circadian rhythm (which is tuned into light and a 24-hour cycle of sleep-wake stages), alterations in sleep patterns can negatively affect the body’s natural melatonin and serotonin production (further impacting sleep and mood) and shift the body’s hunger hormones. (Yes, lack of sleep can ruin your diet. The same is true for too much sleep. Goldilocks was on to something with wanting things just right.)

So, what is optimal sleep? First, it is worth highlighting that healthy sleep will embody several sleep stages. The first is when the body transitions from beta rhythms during the awake state to more calming alpha rhythms (8-12 Hz) that instigate a slowing heartbeat and muscle relaxation. This is where you may not even realize you’ve begun to doze. The second stage of sleep deepens the rhythms with waves of 12-14 Hz which occur in bursts called sleep spindles. The third stage is accompanied by delta waves, also known as slow-wave sleep (SWS). Finally, the most famous stage of sleep is where dreams occur and the eyes move (or REM for rapid eye movement), which makes up about 20% of sleep.

Here’s the thing: People at age 60 experience a 50% decline in stage 3 sleep compared to when they were 20 and 100% reduction by age 90. This is important because sleep releases growth hormone in stage 3 sleep, and overall, sleep restores immune function, rids waste products via the glymphatic system (including B-amyloid which is a suspected cause of Alzheimer’s Disease), and aids learning and memory consolidation.

Image by senjakelabu29 from Pixabay
Source: Image by senjakelabu29 from Pixabay

Returning to the optimal sleep question, adults ideally reach all these deeper stages of sleep, and younger people would be best to take advantage of getting sleep while they are able to attain maximum stage-3 benefits. Adolescents and children require even more sleep which is critical to their development and long-term health. While adults can do well on 7-8 hours of sleep per night, children need around 9-12 hours, and adolescents between 8-10 hours.

What can you do to enhance your sleep? Try to keep your bedroom free from technology and clutter. Create a Zen place for your rest and try to practice some calming Zen-like rituals. Unplug from the tech devices and keep your room dark. If using a night light, use a warm glow instead of the sunlight-provoking blue lights that are so dominant in tech devices (which stimulate the awake state while decreasing sleep-state hormones). In addition, shut off your brain. Stop the thinking. Release the worry and the replay of the day and concerns about the next day. Practice this essential skill of getting quiet while awake. You can do some light stretching and deep breathing before bed. Then relax every muscle in your body as you begin to rest. Take a deep breath, hold it for eight seconds, and then slowly release. With each exhale, imagine every muscle from head to toe relaxing like pudding.

You can also try meditation apps or calming music set on a timer. If you really cannot let go of the racing thoughts or things you’re afraid you’ll forget to do, write it on a list for tomorrow. You will find what works for you and hopefully you can create a culture in your family, and at your workplace, that embraces the health and power of sleep.

If you have challenges with sleep terrors, nightmares, sleepwalking, and/or trauma, please seek help. Cognitive behavioral therapy, trauma recovery, and some of the sleep hygiene tactics described here have been shown to help.