Importance of Sleep to Health
Getting enough sleep among the top three most important thing you can do for your health - in addition to exercise and nutrition. Read the top three things you can do to improve health.
Of course, it is best to do all three things. Dr. Hyman says in his book The Ultramind Solution:
"beside eating whole foods and moving your body, getting enough sleep is the most important thing you can do for your health." [page 169]
If you are sleep deprived (and some estimates say 70% of Americans are), then you can get depression, experience reduced cognitive performance, have slower reaction times, and even lead to weight gain and increase risk of diabetes. That is because sleep has a big effect on our hormonal balance -- including the hormones for appetite and insulin for blood sugar control.
Our cortisol levels are higher if we do not get enough sleep. Besides having a detrimental impact on the brain, chronic high cortisol level can lead to weigh gain. MedicineNet.com says ...
"Cortisol stimulates fat and carbohydrate metabolism for fast energy, and stimulates insulin release and maintenance of blood sugar levels. The end result of these actions can be an increase in appetite."
Dr. Kurt Harris' Archevore diet framework listed "Get plenty of sleep and deal with any non-food addictions" as number one on the list. After that there are quite a number of other dietary tips that he gives in his blog as linked.
Lack of Sleep Leads to Obesity and Glucose Intolerance
When you don't get enough sleep, your hormones related to appetite control becomes unbalanced. Lack of sleep can lead to obesity. Study of healthy young volunteers found that their appetite hormone ghrelin was higher when they were deprived 2 hours of sleep.
In addition, insufficient sleep causes blood glucose levels to be out of balance leading to glucose intolerance, a pre-cursor to type 2 diabetes.
A 2007 study had this conclusion ...
"Laboratory studies in healthy young volunteers have shown that experimental sleep restriction is associated with a dysregulation of the neuroendocrine control of appetite consistent with increased hunger and with alterations in parameters of glucose tolerance suggestive of an increased risk of diabetes"
People who do not get enough sleep will feel pain more intensely. So if you have chronic pain, getting enough sleep may help.
When experimental rats were sleep deprived, the antioxidant glutathione levels were decreased in certain parts of the brain.
How Much Sleep?
From the way our society is running, it appears that some people think sleep is partially optional. But sleep is essential, just like food and water. We can not live without sleep. After days without sleep, we will start to hallucinate.
Although individual needs vary, most people need seven to eight hours of sleep. Your body will tell you when and knows how much sleep it need. It is a self-regulating organism. But modern advances such as the alarm clock hampers this regulation.
In an ideal situation, your body should wake up on its own. If you are woken by an alarm clock, most likely you are not getting enough sleep. You are cutting short the body's desire for the necessary sleep.
Your body's hormonal system also runs on the natural day/night cycle. Modern advances such as modern light (including street lights) can hamper this natural cycle. At night, the body produces more melatonin, the sleep regulating hormone. With light, melatonin production is suppressed. That is why it is important to sleep in total darkness.
Your body will be able to compensate for the lack of sleep to a certain extent -- such as sleeping in and catching up with the sleep debt on the weekends. That is why on weekends (when you don't turn on the alarm), your body naturally will sleep longer to make up for the lost sleep. If you are naturally waking up at the same time on the weekends as you do in the weekdays, then that is a good sign that you are not sleep-deprived.
Some people may feel sleepy during the day even if they are in bed for 8 hours. This can occur if sleep is interrupted by sleep apnea (where airway being blocked) or other causes. You should check with your doctor.
Dangers of Lack of Sleep
If your sleep deprivation is bad enough, you body will start falling asleep during the day and sometimes at dangerous situations such as while driving. It is estimated that 100,000 car crashes a year is due to drowsiness or fatigue.[source]
Lack of sleep is not only harmful to your self-health, but it can be a danger to others.
Media has reported several incidents when air traffic controllers fell asleep on the job, forcing planes to land without clearance or guidance. This occurred during the night shift, which understandably is tough on the sleep cycle.
Dr. Hyman writes ...
"when I learned that shift work (like I did in when I worked in the emergency room) leads to a shortened life expectancy, I quit." [page 169]
Such shift work not only reduces the number of hours of sleep, but it reduces the quality of sleep (as measured by amount of REM sleep). This is because their work schedule is out of sync with the body's circadian rhythm. Some study show that shift work can increase cardiac risk by 40%. That is why many countries including Europe has legislation that limits the amount of shift work, provide free health assessment, and a certain amount of vacation time. [reference]
Cardiac risk is also increased if you work long hours (even if it is not shift work). MSNBC reports that working more than 11 hours per day increases the risk of heart disease by 67%. The Japanese has a term called "Karoshi" which refers to sudden cardiac death from overwork.
In fact, if you have to sacrifice dinner or sleep. It is better to skip dinner and sleep instead. Your body will expire faster without sleep than without food. If you google how long a person can survive without food and how long a person can survive without sleep, you will see. Although no one has tried it so there is no real answer.
But it is said that a person generally can survive three times as long without food than without sleep. Rats deprived of sleep die within 11 to 32 days. [reference]
Even if you skip sleep for 24 hours, you will be more impaired than if you skipped food for 24 hours. In fact, lack of sleep affects blood sugar. So diabetics should get even more sleep.