No one has ever described what healthy sleep is better than William Shakespeare.
A little over 400 years ago he penned the lines, "Sleep that knits up the raveled sleeve of care, the death of each day's life, sore labor’s bath Balm of hurt minds, great nature's second course, Chief nourisher
in life's feast." - William Shakespeare, Act 2, Scene 2, Macbeth.
Wonderful words..."knits up the raveled sleeve...labor's bath balm of hurt minds...nature's second course...chief nourisher in life's feast".
What a blessing it is to be able to slip under the cool sheets and lie your head on the pillow and drift off into dreamland after a long, hard day.
Ever thought about what happens in our bodies and minds that make us sleepy, makes it hard to keep our eyes open, hard to focus, hard to think, just want to lie down, so tired, just let me sleep? And what is it about sleep that restores us; awakened refreshed, alert and ready for another day?
Some of these questions are still unknown with a lot of research still being conducted. But we will try to cover what is known about sleep and how it effects our physical and mental health, our feelings, our productivity, our grades in school, our relationships and so much more.
Healthy sleep, as used here, refers to restful, uninterrupted, deep sleep that restores and refreshes the mind and body.
We'll start with what is known about sleep and dreaming, what happens when we are sleep deprived and how we can ensure healthy sleep to enhance our quality of life.
Photo: Little Bear Sleeping by Schani
All this is well and good but what is it that makes us sleep; that makes us NEED seven or eight hours of healthy sleep every day? Why can't we just pop more energy pills, eat more carbs, drink coffee and keep going?
Our desire to stay awake longer, do more, have more fun or drive straight from Virginia to Florida non-stop isn't a matter of willpower or nutrition or gallons of coffee. It comes down to chemistry. As we will see, all brain function, which is to say, all bodily function, is chemistry.
There is a natural chemical called adenosine that builds up in our blood as our wake time increases. Neurologists would say it is an "inhibitory neurotransmitter, that (they think) plays a role in promoting sleep
and suppressing arousal, with levels increasing with each hour an organism is awake".
It seems we just can't avoid the big words in this subject. OK, an inhibitory neurotransmitter is a chemical that decreases the electrochemical activity of neurons, meaning that the signals or messages between neurons and another cell get dampened or attenuated. Serotonin is another well known inhibitory neurotransmitter.
Back to adenosine. It builds up in the blood while awake and gets broken down in the body while we sleep. The working hypothesis might be that this chemical is what the body uses to keep track of lost sleep and forces us to sleep when we need it.
Taking the hypothesis a step further, it may be that the accumulation of adensine could explain why we build up a "sleep debt" that must eventually be paid for by sleeping longer than normal until the debt is paid.
It is not possible to adapt to getting less sleep than our body needs. Sleep deprivation will be reimbursed one way or another; either by giving yourself restoring healthy sleep or causing a breakdown in some critical system, at which time, we will be forced to sleep.
The first part is easy. A large amount of research by professionals who study these things, show that men need between seven and eight hours of sleep and women, a bit less, at six to seven hours. That six to seven hours for women refers to adult and/or elderly women.
Incredible as it sounds, after reviewing over 300 studies, the National Sleep Foundation now claims that newborns and infants need as much as 14 to 17 hours and 12 to 15 hours respectively. Toddlers and preschoolers can get by on 11 to 14 and 10 to 13 hours respectively.
Elementary school age children need 9 to 11 hours and from teenage years on, the number is between 8 and 10 hours with 8 hours being recommended for adults and senior citizens.
We're not talking about catnaps and fitful sleep; for healthy sleep, it has to be good, uninterrupted continuous sleep.
Restoration starts taking place about two and a half hours into a good sleep. This goes to the fact that sleep is not a steady state process; it occurs in stages and certain things happen in each stage.
The experts aren't sure exactly why, but if we get less than the optimal amount of healthy sleep and we increase our risk of arterial aging and heart attack.
According to Dr. Mehmet Oz, in his book, "You! The Owners Manual", adequate sleep greatly contributes to heart and brain health and can make us up to 3 years younger. Click on the book image to the right to get your own copy of his book.
Lack of sleep sets up a stress response, with cortisol being released into the blood stream thus increasing the risk for arterial scarring and plaque buildup.
A good night of healthy sleep is one of the most crucial things we can do for our body.
Inadequate sleep reduces our cognitive abilities, making us less mentally aware. Lack of sleep results in us making bad choices.
When we are fatigued we eat more and tend to eat more of the wrong stuff. We crave sugar when we're tired.
There is a "feel good" hormone called serotonin, a neurotransmitter. It's a chemical released in the brain and it has a role in the modulation of anger, aggression, body temperature, mood, <b>sleep</b>, sexuality, appetite, and metabolism. All very important functions to us human beings.
If we don't get our required daily allowance of sleep, our brain doesn't release enough serotonin. So a mechanism kicks in that makes us try to compensate by taking in more foods with sugar or really harmful substances like tobacco.
Sleep deprivation also contributes greatly to accidents and makes us more accident prone. I can attest to that first hand. Driving home early one morning after working a night shift I saw a guy die when his car hit the guard rail, flip over and roll a few times. I found out later that he had fallen asleep at the wheel.
Think about it; one minute you're driving down the freeway and a second later you're facing eternity.
Photo: Crash test dummies don't need sleep: we do!
Here's one more. The brain plays a big role in gastrointestinal function. Want to eat less, sleep more. Here's how it works. A hormone called ghrelin tells our brain when we're hungry and another called leptin tells our brain when we're full.
When we don't get enough sleep, more ghrelin is released and less leptin is released. So lack of sleep disrupts the proper control of these two hormones, thus causing us to overeat. Who would have thought
that the current obesity epidemic might be linked to not getting enough sleep?
Environment matters and it's really simple. The bedroom is not your office, not your TV room, not your dining room or your reading room. For good healthy sleep, the bedroom is reserved for just two things and the first is sleep. I can't remember what the second one is.
So take the TV out of the bedroom, don't bring homework or office work to bed, keep your favorite novel by your easy chair in the den and have your night time milk and cookies in the kitchen. Besides, who wants cookie crumbs in their bed?
Still keeping with environment, lower the temperature and darken the room. Put shades or thick curtains over the windows to keep light pollution out; streetlights, porch lights, car lights and the like. And healthy sleep likes a cool room, not too hot, not to cold; just right.
To the extent possible, schedule sleep. Go to bed and get up at the same time every day. It trains the brain and body to expect sleep and prepare for it. The absolute worst situation for maintaining good, healthy sleep is for those poor souls who work rotating shifts or night shifts.
Because of the way our brains are wired, we have a biological clock that takes environmental cues and makes us most alert during daylight hours and the most drowsy during the early morning hours. It is estimated that about one-quarter of our workforce has to work night shifts.
Statistics show that these workers experience higher sleep disorders, have more accidents, especially auto accidents while driving home from work, have more digestive and cardivascular problems, even fertility and emotional problems.
There is also a body of evidence that says the fatigue of night shift workers can be very dangerous.
There is evidence that the Valdez oil spill, Three-Mile Island and the Chernobyl nuclear power plant meltdown were all linked to mistakes made by fatigued workers. For health's sake, if you work the night shift, look for a new career.
Photo: Oops! Where reactor 4 used to be at Chernobyl
The objective regarding sleep and nutrition is to eat foods that calm the brain and this gets us into amino acids. Food that contains the amino acid tryptophan is a good place to start.
This is the basic material that the brain uses to build serotonin and melatonin, two relaxing neurotransmitters, or as our friends, the neurologists would say, "inhibitory neurotransmitters". Typically protein contains amino acids like tyrosine that perk up the brain while carbohydrates are the tryptophan foods, that tend to relax the brain.
The secret is to eat high protein and medium carbohydrate meals in the morning and afternoon. A complex carbohydrate with a little protein meal would be eaten for dinner. A small bedtime snack would be OK if it
combines the complex carb with protein and calcium. Calcium is like a catalyst that helps the brain convert the tryptophan to melatonin.
At bedtime, "snack" means small; don't pig out before bedtime. Good food that contains tryptophan and thus melatonin are pasta, eggs, tuna, chili, tofu, oats, sweet corn, rice and similar. Or there's always the old standby, skim milk and apple pie.
Obviously, avoid stimulants like coffee, tea and chocolate near bedtime.
Lastly, exercise is always recommended as a daily activity, just not near bedtime. Exercise is a stimulating activity, not a relaxing one. Thankfully, this doesn't apply to sex. Sex is great exercise and burns about 300 calories so, yes, it is very stimulating exercise.
The counterbalance is that it also releases a lot of wonderful, relaxing, "feel-good" endorphins. If your heart's up to it, have at it; you'll sleep like a baby.
We all dream but so far, neuroscience hasn't uncovered much definitive information as to why.
Most dreaming occurs during REM sleep. This means that we dream multiple times during the night since we have between five and seven complete sleep cycles inclusive of the REM stage.
There are interesting differences between dreaming in the early slow-wave states and the REM stage. Essentially, our recall and dream content is different. Someone awakened from slow-wave dreaming will have little recall and if any of the dream is remembered, it is unstructured with no "story".
REM sleep, on the other hand, generally has a complex story and can be recalled in great detail. The imagery and intensity of REM dreams is greatest in the early morning hours but the control mechanism is still unknown and is the subject of much research.
"Bad dreams" are more common in REM sleep, having complicated stories with negative connotations. Conversely, slow wave dream content is less visual and emotional. A strange finding is that the true nightmares only occur in slow wave sleep; another unknown concerning dreams.
In the slow-wave, non-REM nightmares, there is a respiratory decline and paralysis. In children night terrors (pavor nocturnus) sometimes occur, lasting 1 -2 minutes. The child may wake up screaming but will have no recall of the nightmare.
In adults slow wave nightmares are referred to as incubus (demons) sleep but, as with children, there is no memory of the dream. If there is any recollection, it is usually short with no story; just a single horrifying event.
Another finding is that REM dreaming only occurs in humans and animals with neocortex, the outer layers of the brain hemispheres. A common theory is that REM sleep is necessary for the consolidation of memory and if we prevent REM sleep, we prevent consolidation of events into long term memory.
All neuroscientists agree that something important must be going on with sleep and dreaming since we spend one-third of our lives engaged in it. In a single stage of sleep, ten separate nuclei and six separate neurotransmitters have been identified, confirming that the structure and function of sleep and dreaming is incredibly complex.
The bottom line is that we still have no definitive, provable reason why we dream or sleep.
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