Are you getting enough sleep to stay in good health? Studies suggest that sleep loss for less than 7 hours per night may have wide-ranging effects on the cardiovascular, endocrine, immune, and nervous systems.
The Importance Of Healthy Sleep
One of the most important principles of Ayurveda is the principle of the three sub-supporting pillars of life, called Upastambha. Those three pillars are diet (Aahar), sleep (Nidra) and celibacy (Brahmacharya) or control of the sexual urges. These three pillars execute an important role in maintaining health.1
Sleep has its importance in leading a healthy life. By getting good and sufficient sleep, one can be ready for new challenges enthusiastically. A sound sleep in the night regenerates the power of the mind and body to accept new challenges, maintains health, proficiency and emotional wellbeing.2
Sleep loss or insomnia (Nidranasha) is the difficulty in initiating or maintaining sound sleep or waking up early without complete sleep with tiredness and exhaustion. The concept of “unsatisfactory sleep” was developed by the American Medicine Institute in 1979.3 According to which insomnia corresponds to the complaint of insufficient sleep almost every night or by being tired after the usual sleep time.4
Signs And Symptoms Of Insomnia (Nidranasha)
Ayurveda describes sleep loss or insomnia (Nidranasha) as a symptom, disorder and even sometimes as a complication of certain diseases. Peculiar symptoms arising during sleep loss are yawning, body aches, lethargy, headache, giddiness in the head and eyes, apathy, fatigue, indigestion and diseases produced by Vata dosha.5 Troubled sleep can lead to unpleasantness, emaciation, weakness, impotency, terminating in death.6 According to Charaka, vigil during the night causes roughness in the body. Obesity is also related with improper sleep and diet.7
Research concludes that women suffer from more sleep-related complaints than men and it is more prevalent with both the onset of menses and menopause.8
What Happens When You Don’t Sleep
There are several consequences to sleep loss which can lead to more serious problems down the road.
1. Premature Aging
Lack of sleep is one of the worst things for your skin. It isn’t called beauty sleep for nothing. Researchers found that women who were sleep deprived had twice the level of skin aging than those who slept well. This meant finer lines, uneven skin tone and slackening of the skin. In one research study, it was seen that the faces of sleep deprived individuals had more hanging eyelids, redder eyes, more swollen eyes, darker circles under the eyes, paler skin, more wrinkles and fine lines and more droopy corners of the mouth.
They looked sadder than after normal sleep. The results show that sleep deprivation affects the features relating to the eyes, mouth, and skin.9
Insomnia or sleep loss can be an overlooked culprit that triggers headaches and migraines. Migraines can be triggered by sleepless nights, and “36 to 58% of people with sleep pane wake up with nondescript morning headaches”. Studies demonstrated that short sleep group, who routinely slept six hours per night, exhibited more severe headache patterns and sleep-related headache.10
3. Inability To Learn
Researchers believe that sleep affects learning power adversely. A study conducted on young volunteers showed that there are dynamic, compensatory changes in cerebral activation during verbal learning after sleep deprivation.11 Another study showed that sleep within 30 hours of training is absolutely required for improved performance.12
4. Obesity Or Weight Gain
When a person sleeps less than seven hours a night there is a dose-response relationship between sleep loss and obesity: the shorter the sleep, the greater the obesity, as typically measured by body mass index (BMI) weight in kilograms divided by height in meters squared.
In a study of 500+ people, it was seen that by age 27, individuals with short sleep duration (less than six hours) were 7.5 times more likely to have a higher body mass index, after controlling for confounding factors such as family history, levels of physical activity, and demographic factors.13 In another study on a large population-base it was observed that those who slept 7.7 hours had the lowest BMI; those with shorter and longer sleep duration had progressively higher BMI. The study found that sleep insufficiency increased appetite. Sleep insufficiency was associated with lower levels of leptin, a hormone produced by an adipose tissue hormone that suppresses appetite, and higher levels of ghrelin, a peptide that stimulates appetite.14 Effects of sleep deprivation on the sympathetic nervous system and/or hypothalamic hormones also influence appetite and increased hunger and appetite, especially for calorie-dense foods with high carbohydrate content.15 Obesity also contributes to obstructive sleep apnea. This most likely occurs through fat deposition in airways, causing them to narrow.
Sleep also plays a key role in energy metabolism. Importantly, a study demonstrated physiological and behavioral mechanisms by which insufficient sleep may contribute to overweight and obesity.16
5. Poor Vision
Lack of sleep is one of the leading causes of eye spasms which results in vision loss. Sleep deprivation hinders the proper performance of many essential tasks and in extreme situations (machine operation or vehicle driving). If you are awake for a longer period then you are likely to experience visual errors or hallucinations such as tunnel vision, double vision, and dimness.17
6. Heart Disease / Cardiovascular Morbidity
Sleep loss and sleep complaints are associated with heart attacks (myocardial infarction) and perhaps stroke, according to several large epidemiological studies.18 Several potential mechanisms could explain the link between sleep loss and cardiovascular events, including increased blood pressure, sympathetic hyperactivity or impaired glucose tolerance.
Experimental data shows that acute sleep loss (3.6 hours sleep) for one night results in increased blood pressure in healthy young males. This is evidence of the association between sleep loss and cardiovascular disease.19, 20
7. Slow Reaction Time
A study conducted on male college student athletes showed that sleep deprivation adversely affects cognitive function such as reaction time.
Reaction time is severely impeded when one doesn’t get enough sleep. Researchers did two tests that require quick decision-making, in which some were allowed to sleep between tests, while others were not. Those who slept did better the second time and those who had not did worse so their reactions slowed down.21
8. Diabetes And Impaired Glucose Tolerance
Impaired glucose tolerance, which is a precursor to diabetes, is manifested by glucose levels rising higher than normal and for a longer period after an intravenous dose of glucose. In the Sleep Heart Health Study, which is a community-based cohort, adults (middle-aged and older) who reported five hours of sleep or less were 2.5 times were more likely to have diabetes, compared with those who slept 7 to 8 hours per night.22 Those reporting six hours per night were about 1.7 times more likely to have diabetes.
Both groups were also more likely to display impaired glucose tolerance. Adjustment for waist girth, a measure of obesity, did not alter the significance of the findings, suggesting that the diabetes effect was independent of obesity.
Prolonged sleep deprivation suppresses immune system function which results in the breakdown of host defenses against indigenous and pathogenic microorganisms.23 The Study showed that even a modest disturbance of sleep produces a reduction of natural immune responses and T cell cytokine production.24
10. Economic Risk-Taking
The results of a study suggest that a night of total sleep deprivation affects the neural mechanisms underlying economic preferences independent of its effects on vigilant attention.
“A single night of sleep deprivation evoked a strategy shift during risky decision making such that healthy human volunteers moved from defending against losses to seeking increased gains”, researchers concluded.25
11. Excessive Urination
Excessive urination at night (called nocturia) is a common symptom of sleep loss. A study conducted in children, confirmed the importance of sleep in the normal circadian regulation of urine output. It demonstrated a significant increase in urine production during sleep deprivation in healthy children aged 8–12 years.26 Nocturia may be linked to bedwetting in children and in adults.27
Attention tasks appear to be particularly sensitive to sleep loss. Adequate sleep is necessary if you want to stay alert and attentive. Otherwise, you enter an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep, and your ability to pay attention is also diminished.28,29
Poor or inadequate sleep can cause irritability and stress, while healthy sleep can enhance well-being. A study investigated the relationship between sleep loss and emotional reactivity in medical residents. It was seen that sleep loss amplifies the negative emotive effects of disruptive events while reducing the positive effects of goal-enhancing events.30
14. Memory Problems
Sleep disruptions in the elderly can lead to structural changes in the brain that are associated with impaired long-term memory. Sleep-related memory deficits have been observed in the general adult population as well. As early as 1924, researchers noticed that people who slept more forgot less.31,32
15. Car Accidents
Drowsy driving accounts for thousands of crashes, injuries and fatalities each year, according to the National Highway Traffic Safety Administration. Pilots, truck drivers, medical residents, and others required to stay awake for long periods of time show an increased risk of crashes or near misses due to sleep deprivation.33
16. Less Effective Vaccines
Lack of sleep weakens the effectivity of vaccines. Vaccines help in developing immunity by creating antibodies against a specific virus. When you don’t sleep, your immune system is compromised, and this doesn’t work well. In one study, 19 people were vaccinated against Hepatitis A. Ten of them got eight hours of sleep the following night, while the rest pulled an all-nighter. Four weeks later, those who had slept normally had levels of Hepatitis A antibodies almost twice as high as those who had been kept awake.34
Another study also found that sleep has a supportive influence in the very early stage of an adaptive immune response to a viral antigen. It was concluded that “sleep should be considered an essential factor contributing to the success of vaccination.”35
17. Impaired Speech
In sleep loss conditions, speech becomes slurred and you may sound like you had too much drunk. One study kept volunteers awake for 36 hours. They showed a tendency to use word repetitions and clichés. They spoke monotonously, slowly, and indistinctly, and they were not able to properly express and verbalize their thoughts.36
Lack of sleep increases your risk of catching a cold. When a group of 153 people were exposed to a common cold, it was seen that those who had less than seven hours of sleep in the two weeks prior were almost 3 times more likely to get sick than those who had 8 or more hours of sleep.
How well you sleep is also a factor in susceptibility to cold. Those who spent 92% of their time in bed actually asleep were 5.5 times more likely to catch a cold than those who had been peacefully slumbering 98-100% of the time they were in bed.37
19. Gastrointestinal Problems
Regular sleep loss is a reason for the development of both Chrone’s disease and inflammatory bowel syndrome, which affects an estimated 10-15% of people in the U.S. Patients with Crohn’s disease are twice as likely to experience a relapse when they weren’t getting enough sleep.38
20. Depleted Sex Drive
Lack of sleep kills a person’s sex drive. Testosterone is an important component of sexual drive and desire in both women and men. Sleep loss reduces testosterone levels in males. Low sex steroid hormone concentrations have been associated with sexual dysfunction.39 Sleeping increases testosterone levels, while being awake decreases them. In a study conducted on women between the ages of 45-50, sleep deprivation and disturbed sleep was found associated with reduced libido and sexual dysfunction.40 Erectile dysfunction and overall sexual dysfunction were highly prevalent in males with suspected sleep apnea.41
21. Lower Pain Endurance
Lack of sleep often makes pain worse. One study found that when subjects were kept awake all night, their pain threshold, the amount of painful stimulus that they were able to endure was lower.42
22. Sloppiness Or Lack Of Organization
Lack of sleep can make your work sloppy. One study found that one sleepless night contributed to a 20-32% increase in the number of errors made by surgeons.43 People playing sports that require precision – shooting, sailing, cycling, etc. – also make more mistakes when they’ve been awake for extended periods of time.44
Disrupted circadian rhythm and reduced immunity are direct results of sleep deprivation. Preliminary research seems to indicate that people who don’t get enough sleep are at increased risk for developing certain kinds of cancer, most notably colon and breast cancers.45,46,47 Short sleep duration and poor sleep also been linked to higher levels of β-Amyloid, a biomarker for Alzheimer’s Disease.48
24. Genetic Disruption
Poor sleep disrupts normal genetic activity. Researchers found that after sleeping less than six hours per night for one week, 700 genes were not behaving normally, including some that help govern immune and stress responses. Just one week of less-than- ideal sleep is enough to make some of your genetic activity go haywire.49
25. Unhappiness, Depression, Anxiety And Alcohol Use
Even a small levels of sleep deprivation over time can chip away at your happiness and pave a way to depression, anxiety condition. In a classic study led by Nobel Prize-winning psychologist Daniel Kahneman, a group of 909 working women kept detailed logs of their moods and day-to- day activities.
While differences in income up to $60,000 had little effect on happiness, a poor night’s sleep was one of two factors that could ruin the following day’s mood. The other was tight deadlines at work.50
Another study reported, a higher level of marital happiness among women with more peaceful sleep.51 Insomniacs are also twice as likely to develop depression, and preliminary research suggests that treating sleep problems may successfully treat depressive symptoms.52 Sleep loss is also associated with adverse effects on mood and behavior. Adults with chronic sleep loss report excess mental distress, depressive symptoms, anxiety, and alcohol use.53,54,55
A meta-analysis of 19 original articles found that partial sleep deprivation alters mood to an even greater extent than it does cognitive or motor functions.56 Several studies of adolescents, found that inadequate sleep is associated with higher levels of depressed mood, anxiety, behavior problems, alcohol use57,58,59 and attempted suicide.60 On the other hand, a large, 3-year longitudinal study of more than 2,200 middle school students (ages 11 to 14) found that self-reported sleep loss was associated with more depressive symptoms and lower self-esteem over time.61 The study measured sleep loss using a single question about sleep duration on school nights and measured depressive symptoms and self-esteem by the Children’s Depressive Inventory and the Self-Esteem Questionnaire, respectively.
26. Sleep Loss, Disease Mortality And Death
Sleep deprivation may cause an increased risk of death. People who consistently do not get 7-8 hours of sleep are more likely to die during a given time period .i.e. sleeping too little – or even too much – is found associated with a higher risk of dying sooner than you otherwise might.62 Sleep loss is associated with increased age-specific mortality, according to three large, population-based, prospective studies.63,64,65 Deaths in short or long sleepers were compared with those who slept 7 hours (the reference group), after adjusting for numerous health and demographic factors. Sleeping 5 hours or less increased mortality risk, from all causes, by roughly 15 percent. The largest American study showed that progressively shorter or longer sleep duration was associated with greater mortality. Other epidemiological studies suggest that sleep-loss related mortality is largely from acute heart attacks.66