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Insomnia and Sleep Deprivation: The Case For A Good Night's Sleep

Medically reviewed by Carmen Fookes, BPharm. Last updated on Aug 12, 2022.

Why Do We Sleep?

Along with nutrition, water, and exercise, sleep is necessary to live a long, healthy, and happy life. Despite the fact that we spend around one-third of our lives sleeping, scientists have yet to definitely answer the question "Why do we sleep?" Evidence so far suggests it is far more important than we have previously realized. Many refer to it as our second state of being - a recurring state where complex and essential physiological processes take place. But we still don't have all the answers.

One thing is clear - a persistent lack of sleep or chronic insomnia is hazardous to our health.

How Much Sleep Do I Need?

The National Sleep Foundation has identified 4 key indicators of good sleep quality, which are:

  • Sleep latency: how long it takes you to fall asleep
  • Sleep waking: how many times you wake during the night
  • Wakefulness: how many minutes you spend awake during the night
  • Sleep efficiency: the amount of time you actually spend sleeping while you are in bed. For optimal health benefits this should be 85% or more of the time in bed.

The National Sleep Foundation also stipulates what duration of sleep is appropriate according to age. Although some people may experience sleep durations outside the recommended range, the experts believe that habitual deviations far from the normal range may be severely compromising for a person's health and well-being. Appropriate sleep durations, per age are:

  • Newborns: between 14 and 17 hours
  • Infants: between 12 and 15 hours
  • Toddlers: between 11 and 14 hours
  • Preschoolers: between 10 and 13 hours
  • School-aged children: between 9 and 11 hours
  • Teenagers: between 8 and 10 hours
  • Young adults and adults: between 7 and 9 hours
  • Older adults: between 7 and 8 hours.

Attention Deficit/Hyperactivity Disorder (ADHD) And Sleep

The relationship between ADHD and sleep is complex. Research shows sleep deprivation worsens ADHD symptoms such as inattention and hyperactivity. Other studies link ADHD to a number of different sleep disorders such as periodic limb movements (PLM), narcolepsy and sleep apnea.

Particularly in children, it may be difficult to work out which came first...the ADHD or the sleep disturbance. While adults are more inclined to be sluggish when tired, children tend to overcompensate and speed up, becoming moody, emotionally explosive or aggressive. Questions regarding the quantity and quality of sleep should always form part of an assessment of a child with suspected ADHD, and attention should be paid to improving sleep in children who fall below the National Sleep Foundation's sleep duration recommendations.

Alzheimer's Disease And Sleep

Sleep issues associated with agitation are the main reason people with Alzheimer's Disease (AD) are placed in institutional facilities. Shorter sleep durations, fragmented sleep, elevated rates of sleep-disordered breathing, and sun-downing - an increase in agitated behavior in the late afternoon/early evening - all commonly occur with AD.

Poor sleep is also thought to increase the risk of developing AD. Cognitively healthy older adults who scored highly on a "sleep disturbance index" (which took into account sleeping problems and fatigue, sleep medication use and recent difficulty with sleeping) were 23% more likely to develop dementia within four years than individuals reporting good sleep. Another study showed shorter sleep duration was associated with a greater degradation of β-amyloid proteins into amyloid plaques (these are the hallmark of AD and are toxic to nerve cells). Deep sleep appears crucial for allowing cerebrospinal fluid to "flush away" AD-causing toxins. People possessing a particular gene associated with obstructive sleep apnea are also more likely to develop AD and heart disease.

Sleep, Sleep Apnea And Cardiovascular Risk

Our heart beats on average 4,800 times a day, every day of our lives. During sleep, our heart beat reduces, and this may be the key to maintaining good cardiovascular health.

Research has found that the risk of a heart attack is more than doubled and the risk of stroke quadrupled in people with sleep disorders. It is well documented that people with sleep apnea have poor heart health. Sleep deprivation is also associated with high blood pressure, coronary heart disease and diabetes. Even one night's poor sleep can increase blood pressure the following day.

Experts aren't exactly sure how poor sleep impacts on heart health but suggest it may increase sympathetic nervous system activity the next day. Inadequate sleep also disrupts important biological processes such as glucose metabolism and increases inflammation.

The Relationship Between Sleep And Obesity

There's an old saying, "You are what you eat". Well, perhaps that should be "You are how you sleep", instead.

More and more research indicates there is an association between sleep deprivation and weight. In general, the less you sleep the more likely you are to put on weight.

Experts aren't sure if the relationship between poor sleep and obesity has to do with the extra hours available to eat at night, people feeling too tired to exercise, or due to the disruption of key hormones that control appetite.

Unfortunately, the more weight somebody puts on, the higher their chances of developing other conditions such as sleep apnea, cardiovascular disease, and diabetes; all of which can interfere with sleep to varying extents. People may find themselves stuck in a self-perpetuating cycle of continued weight gain as a result of their ongoing sleep deprivation.

If your weight gain seems to be related to your sleep habits, make changes early on. Partake in exercise during the day, every day, and choose healthy options instead of sugar-laden and fried foods. Avoid stimulating activities just before bed and make sure your bedroom is conducive to sleep. Turn to meditation or podcasts that allow your mind to wind down and succumb to sleep, rather than taking a sleeping pill.

Sleep Deprivation Increases The Risk of Type 2 Diabetes

Doctors have known for years that poor sleep disrupts the body's ability to regulate and metabolize glucose. A sleep deprivation study showed healthy adults restricted to just four hours sleep a night had a 40% lower ability to break down glucose than participants allowed a full night's sleep. When these sleep-deprived subjects were fed a high-carbohydrate breakfast, their high glucose levels persisted longer than those who were fully rested, indicating their bodies were not processing glucose as well.

Experts believe a lack of slow-wave sleep underlies this discrepancy in glucose metabolism. When we enter a deep sleep state, our brain activity decreases and uses less glucose. It is also the time during which growth hormone is released and levels of the activating hormone, cortisol, go down. One Japanese study reported a two-to-three fold higher risk of late onset, type 2 diabetes within eight years in 2,649 male employees of an electrical company who reported sleep disturbances.

Talk with your doctor if you are experiencing any symptoms of diabetes which may include increased thirst, frequent urination, persistent tiredness, numbness or tingling in the toes, blurred vision, or slow-healing infections.

Sleep And Mood Go Hand In Hand

It is not hard to tell if one of your friends, family members, a colleague or your partner has had a bad night's sleep. Sleep-deprived individuals are typically irritable, short-tempered, and prone to stress. After a good night's sleep, their mood miraculously returns to normal.

Sleep and mood are closely related. While the odd night's missed sleep tends to only have a temporary affect, chronic poor sleep greatly increases the risk of developing a mood disorder such as anxiety or depression. One survey reported a 4-times greater chance of developing depression in young adults who reported insomnia three years earlier. Doctors who reported insomnia at medical school were twice as likely to have developed depression forty years later.

In addition, mood and certain mental states also affect sleep. Conditions such as anxiety and post-traumatic stress disorder (PTSD) increase agitation and arousal, making it harder to sleep. Worry and sadness also keep people from sleeping well. Addressing the issue of sleep is a vital component in the treatment of mood disorders. Sleep problems that persist despite treatment are associated with a lower quality of life and an increased risk of relapse and suicide.

Sleep Boosts Your Immune System

Our natural response when we are sick is to stay in bed and sleep. In fact, evidence supports the popular belief that "sleep helps healing" with studies showing the production of immature T cells - a type of white blood cell that plays a central role in immunity - peak during early nocturnal sleep. Sleep is also vital for the regulation of proinflammatory cytokines which are tiny proteins directly involved in inflammation. Although our bodies require small amounts of proinflammatory cytokines to fight infection, poor sleep can lead to overproduction and a chronic low-grade inflammation that blunts our immune response.

In addition, during illness the cells of our immune system also produce substances that promote sleepiness, which experts believe promotes inactivity and allows our immune system to function to the best of its capacity, increasing our chance of survival.

The Right Amount Of Sleep Can Make You Live Longer

Pooled study results show your chances of living a long and healthy life are significantly decreased with poor sleep. Getting five hours or less sleep per night increases your chances of dying from any cause by approximately 15%.

Although sleep quality generally decreases as we age, a study that specifically looked at the oldest of old adults (aged 85 to 105 years) showed their amount of stage N3 (slow wave, deep sleep) was comparable to that of people aged 60 to 70. In addition, the group over the age of 85 who were more strict with their sleep and wake schedules, also tended to have a better lipid profile than adults of a younger age.

One thing is clear, if you are having trouble sleeping, don't ignore it. Mention it to your doctor at your next visit or see a sleep specialist. Many people drastically underestimate the impact sleep problems can have on their physical and mental well-being, but actively doing something about your poor sleep could greatly lengthen your life.

How To Help Children Sleep

The younger your child is, the easier it is to establish a bedtime routine. However, it is never too late. Consistency is the key to ensuring your child has a good nights sleep, every night.

  1. Set a bedtime that is not too early, nor too late. Children aged 5-6 years should go to bed around 7.30-8.00pm, whereas older children up to the age of 11, should be in bed by 9.00pm.
  2. Start preparing your kids for bed, 60 minutes before their bedtime. Turn off the TV, computers, or other stimulating devices; shower or bathe them; get them to clean their teeth and go to the toilet; and read a story before a goodnight kiss and lights out.
  3. Keep noises to a minimum and ensure your child's room temperature is around 65°F (18°C). Allow them to take a comfort object - such as a soft toy or blanket - to bed with them, and provide a small dim night-light just in case they get up in the night.
  4. Relaxation and calming exercises or podcasts that teach deep breathing and visualization, may also help children to relax.

Improving Sleep In Adults

Many of the same techniques used in children to promote a good sleep - such as establishing a consistent bedtime and winding-down for 60 minutes before sleep - should be applied by adults as well. In addition, adults should also:

  • Avoid caffeine, nicotine and alcohol from late afternoon onwards
  • Talk to your doctor or pharmacist about managing your medications and the possibility of switching those that may be potentially stimulating from evening to early morning
  • Increase levels of physical activity during the day (but not just before bedtime)
  • Limit daytime sleeping; if a nap is needed, make sure it is short and not too late in the day
  • Treat any underlying conditions such as sleep apnea, depression, anxiety, or pain that may be contributing to sleep problems
  • Early morning exposure to bright light (either natural or via a specialized light box) soon after waking may improve night-time sleeping
  • Actively try to increase your quantity and quality of sleep without the use of sleep medications. Seek out a sleep specialist or download many of the sleep-specific guided meditation podcasts available on the internet.

Your long-term health depends on a good night's sleep. Sleep tight.

Finished: Insomnia and Sleep Deprivation: The Case For A Good Night's Sleep

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Further information

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