Medically Reviewed by Vincenta Faulkner, RD, CNSC, CCTD
There isn’t much that can beat a deep, restorative sleep. The best way to start your day is to get the quality sleep your body craves. We all know the feeling of being tired: midday fatigue, crankiness, changes in our mood and appetite.
Sleep, good or bad, really is the predictor of how our tomorrow will be.
You might think that with so many advancements in medical science, we would have figured out our nighttime snoozes in their entirety. You may be surprised to know that why we sleep, and its exact purpose, is actually not entirely known. However, we certainly know how important it is from both a common sense perspective and a health perspective.
Nevertheless, a rich amount of sleep research has taught us quite a bit about sleep and how it affects our body.
Deep sleep, for example, is a very important stage in our overall sleep cycle. Ensuring that your body gets enough deep sleep may be a crucial part of your health. In fact, there’s been some pretty conclusive research indicating that a lack of sleep may even affect your cholesterol.
What Is Deep Sleep?
As the name suggests, deep sleep is the deepest stage of our sleep cycle. It plays a role in everything from our memory and cognitive function to restoring our energy stores. The science recommends that adults need seven to nine hours of sleep a night. Deep sleep makes up 13-23% of our total sleep, making it essential that we get as much as possible.
To illuminate this crucial function, let’s first examine how the sleep cycle plays out, and discover what role deep sleep plays.
Stage 1 of Deep Sleep
Stage 1 marks our transition into a sleep state. We begin to feel drowsy, our eyelids growing heavier and heavier. Our breathing and heartbeat slow down at a deeper physiological level.
These are the moments just after we tuck ourselves in and before we finally doze off into dreamland.
Stage 1 marks the first of three non-REM sleep stages throughout the night's sleep cycles.
Stage 2 of Deep Sleep
This light stage of sleep is the initial unconscious stage. Like Stage 1, our breathing and heart rate continues to slow down. Our body lowers its temperature, and muscles relax as we settle into an even deeper level of sleep. Brain waves continue to slow and grow deeper in pitch.
Stage 2 constitutes the second part of three non-REM sleep stages, leading us to Stage 3.
Stage 3 of Deep Sleep
Stage 3 is the deepest stage of sleep.
The slowing of our bodily functions reaches the lowest it will reach throughout the cycles over the night; including heartbeat and breathing. Brain waves fluctuate up and down at their highest pitch, slowly oscillating.
This is the final and deepest stage of non-REM sleep.
What Is REM Sleep?
REM stands for rapid eye movement. This stage marks our ascent out of our prior deep state in Stage 3. While still unconscious, our eyes move about, hence the name. If you find yourself dreaming, you’ve reached the REM stage of sleep.
All the previously mentioned functions like heart rate, breathing, brain waves, and so on begin their return to normal, waking levels, only to sink back down as the sleep cycle restarts and continues again throughout the night.
One sleep cycle lasts an average of 90 minutes. The cycle may repeat itself four to five times in a night for most sleepers, with most of our time spent in Stage 2.
Why Is Deep Sleep Important?
Deep sleep is when everything has slowed down, and your body has a chance to dedicate some energy to repairing itself. Our body heals the most and grows the most during this stage, making it an extremely important aspect of our sleep cycle.
You don’t want to wake up in the morning halfway repaired.
In fact, irregular sleep cycles, especially a lack of deep sleep, have many negative effects on the body, including an increase in LDL cholesterol, the build-up of which can increase our risk of heart diseases and stroke.
Here are some ways to improve your sleep cycle and encourage consistent, deep sleep.
Decrease Caffeine Consumption
Like sleep, diet is one of the foundational components of our overall health. A good or bad diet can make all the difference in your health — and your sleep.
Naturally, you can imagine why heightened coffee consumption or other caffeinated beverages would have a negative effect on the quality of our sleep. If you drink a cup of coffee, half of the caffeine in that cup of Joe will remain in your body up to six hours later.
It takes ten hours total for caffeine to leave the bloodstream. Decreasing coffee and other caffeine consumption is a great first step to ensuring we’re getting more deep sleep.
Be Mindful of What You Eat
The relationship between certain foods and the quality of sleep was explored in a study that discovered some interesting findings.
People who consumed a low protein diet reported difficulty falling asleep, unable to enter the initial Stage 1 of deep sleep. Alternatively, people who consumed a high protein diet reported difficulty maintaining sleep, the later stages of sleep like Stage 3.
Our carbohydrate intake is another area in our diet that may impact the quality of our sleep.
In one study, men in a normal weight range with lower carbohydrate consumption reported fewer instances where they had trouble getting good quality sleep. The same rang true for overweight men who consumed fewer carbs, which indicates that a lower-carb diet may help you get better sleep.
Women who followed the Mediterranean diet — lots of whole grains, beans, fish, and vegetables — reported fewer symptoms of disordered sleep as well, finding it easier to fall and stay asleep.
One encouraging study found an interesting relationship between the quality of our sleep and a pre-bedtime ritual of journaling.
Researchers gathered a group of college students who did not report prior sleep disorders. The students were tasked with writing either a to-do list for the following day, or a list of objectives completed that day.
Funny enough, the students who wrote the to-do list were able to get to sleep faster and maintained a less interrupted level of sleep than their completionist counterparts.
Something as simple as putting into context what’s on your plate for the following day may help you soothe your mind, allowing you to get better sleep faster. Break the pen and paper out and make a to-do list for yourself, and you may be able to get better quality sleep.
Use Supplements (Responsibly)
Melatonin is an over-the-counter supplement that encourages better quality sleep. Melatonin is produced by the brain as the sun goes down, building up a drowsiness that eventually helps us get to sleep.
There have been many studies on the effects of melatonin. One study examined melatonin’s effects on people dealing with significant crises in their lives; the participants were cancer patients struggling with insomnia. The study concluded that participants reported better sleep quality due to melatonin supplementation.
Melatonin functions as a cue for our body that it is time for sleep. Many diurnal (active during the day) mammals like humans experience melatonin production as the sun begins to set.
As we age, our pineal gland, which produces melatonin, produces less of it. Researchers found that supplemental melatonin in older people at stages where their body’s melatonin production decreases may be correlated with alleviated disorder sleep symptoms and more restorative sleep. Just be sure to use your supplements responsibly to steer clear of side effects.
Get the Deep Sleep You Need
Your day is too important to be ruined by a poor night’s sleep. Those nights of poor sleep add up and can have real, enduring effects on the quality of our health. We hope that this information on sleep and the subsequent tips encourage you to get those much-needed zzzs.
Zizi is committed to your health, especially when it comes to combating poor cholesterol. More deep sleep may be connected to decreased LDL cholesterol levels, so for people embroiled in that fight, we want to ensure that you’re getting the best quality sleep you can to keep stress levels and cholesterol levels down where they need to be.
Stress is a critical factor keeping us up at night. If you’re concerned about your cholesterol levels, check out our website, where you can learn more about our program that includes at-home cholesterol test kits, supplements to help mitigate your cholesterol, and a heart health course that will bolster your health.
Heart health starts at home, and care comes easy with Zizi.
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