Better Sleep Part-Ⅱ "Impact of sleep on Health"

In this Part-Ⅱ of Better Sleep blog, we are going to discuss the detailed impact of sleep on health. We all know sleep is essential for good health but most of us are not aware of what it actually means. What and how much sleep impacts on our health. So let's check the details one by one.

Sleep and Creative Connection

    You might have heard many stories that scientists and artists making discoveries in their dream. There is well know the story about Paul McCartney that the tune of his 1965 hit "Yesterday" came to him in a dream. Similarly, it is said that famous writer Stephen King once fell asleep on a plane to London and dreamed about an author held captive by a crazy fan. When he woke up, he jotted down the dream and its dialogue on a cocktail napkin. That became the core of his best selling psychothriller "Misery". Another well-known case of Russian chemist Dmitri Mendeleev, who developed the periodic table of elements saw it in a dream first.

    The famous saying "sleep brings insight " is true in the sense that sleep particularly REM or dreaming sleep is a reservoir of creativity. REM sleep, specifically, is the time when mental connections are made and information is synthesized in new and surprising ways. 

    Even a short nap can bring insights. So next time you have a knotty problem, sleep on it. The answer may be waiting to delight you when you wake up! 

Sleep and Performance

    Sleep experts advise that those who want to reach peak performance need to get peak sleep. Sadly athletes are often pressured to forgo sleep to train and meet goals. Most muscle building and tissue repair happen during sleep and that it improves performance. Lack of sleep, in contrast, raises the risk of injury. During sleep, the brain also builds connections that lead to skilled muscle memory. 

    Well-slept players run faster sprints and shoot more accurately than players sleeping less than 8 hours. Improving sleep duration and quality boosts performance in all athletic players. Pro athletes know it best, "Make time for sleep and your body will thank you."

Sleep and Immunity

    Sleep researchers have found that the neurons controlling sleep in the brain are in constant conversation with the immune system. Hormones and neurotransmitters flow back and forth among these cells, adjusting your immune response to your sleep/wake patterns. And what the immune system wants is a good night's sleep.

Your mother said you'd get sick if you didn't get enough sleep, and now sleep researchers are backing her up.

     When you're sick, the immune system prompts your body to sleep more. And when you run short on sleep, your brain cannot stimulate a proper immune response. Sleepless people have fewer cytokines, proteins that fight infection and inflammation. They also produce far fewer cancer-fighting natural killer cells; a single night with four hours of sleep results in a 70 percent drop in these immune system stalwarts. However, one sleepless night is not as bad for your immune response as chronic short sleep night after night, a common problem nowadays. A full night's sleep also bolsters your response to viruses. 

    Sleeplessness may even promote cancer. People with reduced amounts of natural killer cells have a greater risk of dying from a wide range of cancers. Shift work, with its disrupted sleep rhythms, has been connected to breast, prostate, and colon cancers. Scientific studies are suggesting that sleep, or lack of sleep, can have a profound impact on the effectiveness of a vaccine. 

Sleep and Obesity

    Sleep researcher Dr. Eve Van Cauter of the University of Chicago calls sleep deprivation "the royal road to obesity." Sleep is intimately connected to your body's metabolism, including its ability to process glucose (blood sugar). People who are short on sleep need 40 percent more insulin than their rested counterparts. The hormone leptin makes you feel full and drops in people who are sleep deprived, while its complement, the appetite-stimulating hormone ghrelin, increases. Sleeplessness also raises the level of natural endocannabinoids
in the bloodstream: Like cannabis, these chemicals give you the munchies. Sleepless folks eat 300 more calories a day than the well slept. Sleepless folks are hungrier than others, and they tend to reach for sweets, not vegetables.

     Sleeplessness and obesity can be a vicious cycle. Heavier people are more likely to suffer from sleep apnea, which obstructs breathing and fragments sleep. The resulting fatigue can boost hunger, putting on the pounds when you need them the least. Sleep deprivation is connected to a rise in obesity and type 2 diabetes and heart disease. Risk factors are many, and not all are well understood, but one is often overlooked: sleeplessness.

Sleep and Heart

When we are faced with a sudden threat our fight or flight reaction kicks in. Stress hormones flood your body. Your heart beats faster, blood flows faster to your muscles, and your breathing speeds up This reaction is vital in extreme situations, but it comes at a cost to the body. Sleepless people also pay this cost: Their sympathetic nervous systems, which should ramp down at night, stay active, and keep them on high alert. People who don't get enough sleep are at a much higher risk of heart disease, heart attacks, high blood pressure, and strokes.

Sleep-deprived people are two to three times more likely to have calcification in their coronary arteries, a condition that narrows and stresses the blood vessels. In sleep, blood pressure normally drops, but not in the sleep-deprived. This hypertension increases the risk of stroke.

Getting too much sleep-say, more than nine hours-doesn't help and may in fact hurt. Mortality goes up for the overslept as well. The right amount, as always, seems to be seven to nine hours, as sound and uninterrupted as you can make them. 

Sleep and Mental Health

Poor sleep is a hallmark of many mental illnesses, including schizophrenia, depression, and bipolar disorder. Insomnia and disturbed sleep both are precursors to and symptoms of serious psychiatric disturbances including depression, anxiety, and bipolar disorder. Even in small doses, sleeplessness affects a healthy person's emotions and perceptions.  Studies show that people who are short on sleep have an overreactive amygdala that yanks them back and forth between positive and negative emotions.
People who report insomnia are four times more likely to develop major depression than those with healthy sleep. Three-quarters of those who already have depression also suffer from poor sleep. In patients with depression, sleeplessness is a recognized risk factor for suicide.
Most patients with bipolar disorder also have insomnia, particularly just before and during manic episodes. Sleep loss, in fact, can trigger an episode. People with anxiety disorders are also likely to sleep poorly, with sleeplessness worsening their symptoms and making recovery tougher. About half of patients with schizophrenia have insomnia. Sleep disorders are common in people with addictions, contribute ing both to cravings and to problems with recovery. Poor sleep, even in childhood, is a risk factor for addiction later.

Sleep and Memory

In the first century A.D., the Roman scholar Quintilian wrote: "The interval of a single night [of sleep] will greatly increase the strength of the memory... [as] the power of recollection... undergoes a process of ripening and maturing." In recent decades, scientists have been able to test and track this process and have found that sleep, particularly slow-wave sleep, does just what Quintilian said. it strengthens and consolidates memory and learning.

Memory, as we currently understand it, has three basic stages. The first is encoding. Momentary experiences are sent to short term storage within the brain's hippocampus. The second stage is consolidation. Important memories move into the long-term residence in the brain's cortex, where they are integrated with other information. The third stage is retrieval: When you need them, you fetch the memories back into consciousness.

We feed our brain with important and unimportant information during the day, and it seems to actively suppress the insignificant memories. In your waking hours, you are bombarded by external stimuli and a near-infinite amount of unnecessary facts. During sleep, your neurons finally have time to sort through the day's input, keep what's important, and discard the trivia. This happens mainly during slow-wave, non-REM (NREM) sleep, the kind that dominates the early parts of our sleep(and most naps).

Poor sleep is a cause and an effect of dementia, scientists suspect. Studies of healthy elderly people show that those with highly fragmented sleep are far more likely to develop Alzheimer's disease than those who sleep soundly. The toxic protein deposits known as beta-amyloids, which build up in the brains of people with Alzheimer's, are more likely to be found in the frontal lobes of patients with disturbed sleep. Severely disturbed sleep in old age may be an early warning sign of dementia, allowing it to be diagnosed and treated earlier, with better results. 
Sleep doesn't just help you retain information-it also helps you forget. In a process that's not clearly understood yet.