The Importance of Sleep

I get it, sleep comes across as being bit of a boring topic and even hearing the word makes you tired, but although I say sleep is a cornerstone of a fit and healthy lifestyle, I look at it as being more of the foundation. There is not a single tissue in your body, or process in your brain that doesn't benefit from sleep.

After reading this, you might think twice next time you crawl your way out of bed to go to the gym...

A scary example for you is that if your goal is weight loss but you're sleep deficient, up to 70% of the weight you lose will be muscle and not fat. This would mean dieting becoming ineffective.

Lack of sleep is also linked to:

• Cancer

• Heart Disease

• Stroke

• Obesity

• Depression

• Dementia

• Alzheimer's

I talk about this in greater detail further down.

Let's get started...

The Stages of Sleep

We have two basic types of sleep, Non REM and REM (Rapid Eye Movement).

Non REM is subdivided into 4 stages:

• Stage 1 is the transitionary stage of going from wake to sleep and it takes about 3-4% of the night.

• Stage 2 takes 45-50% of the night which is the biggest stage you have.

• Stage 3 and 4 are combined together and are your physical restoration. This is where the largest amount of growth hormone is emitted and is usually at the beginning of the night. Reason being is so that if you only get 3 hours sleep your body is still functional.

REM:

Rapid Eye Movement sleep is the later stage of the night which is the more popular stage of sleep as people have probably heard about it being the stage of dreaming. REM sleep is your mental restoration and your brain is more active than any other stage. This is where you move information from your short term memory to your long term memory.

Sleep is Individual

I myself think it is crazy when clients have said to me that sleep is not that important. Sleep has a bad image problem, as we label people who get sufficient sleep as as being lazy. Restricted sleep feeds into every health issue that we have, for instance, it plays a huge role in the cause of my epileptic seizures.

Sleep deficiency in general and Chronic sleep deprivation both have system wide effects. They lead to things such as cardiovascular disease, dementia, and more. They affect every organ system and every disease state. Cancer cells multiply faster the more sleep deprived you are.

Recommended Hours of Sleep:

The US National Sleep Foundation’s recommendations for nightly sleep are broken down into nine age groups:

• 0-3 months old: 14-17 hours

• 4-11 months old: 12-15 hours

• 1-2 years old: 12-14 hours

• 3-5 years old: 10-13 hours

• 6-13 years old: 9-11 hours

• 14-17 years old: 8-10 hours

• 18-25 years old: 7-9 hours

• 26-64 years old: 7-9 hours

• 65 or more years old: 7-8 hours

Looking at these recommendations shows an adult's average of around 8 hours of sleep a night, but an individual needs to get the right amount of sleep in the right way for their own body. Someone who is inactive due to a health condition may not need the same amount of sleep as an athlete.

The average sleep cycle is 90 minutes long and the average individual has about 5 of these sleep cycles. 5x90 = 450 minutes ÷ 60 is 7.5 hours.

A self experiment is to take your average wake up time and count back 7.5 hours. For instance, if your wake up time is 0630, then aim to get to sleep at 2300. If you still don't feel energetic and awake then add an hour on. Alternatively, you could try and shift your schedule so you can match your chronotype.

Chronotype

15% of the US population are Early Birds, 15% are Night Owls and 10% are Insomniacs.

Early Bird:

Morning - Peak spike of brain activity is in the morning. The early birds best time for their most demanding analytical work.

Afternoon - As the day goes on, the early bird starts to wear down.

Night - When your brain is most tired.

Night Owl:

Morning - Your brain is most distracted, which allows for more creativity.

Afternoon - The night owl gets more productive as the day goes on.

Night - Peak spike of brain activity. The best time for the night owl to solve problems, answer questions and make decisions.

We go through all the Chronotypes throughout our lives. Here are some examples:

• As a baby, they go to bed early and wake up early.

• When children are in primary school they go to bed about 8:30pm and get up about 7:00am.

• Teenagers stay up until midnight and struggle to wake up in the morning.

• At the age of around 20-22 the Chronotype stabilises and stays stabilised until you're about 55-60.

• The reason why older people tend to eat dinner earlier is because their circadian rhythm is telling them to eat earlier as they will be going to bed earlier.

The Evolution of Sleep

In 1942, a survey was done to show the average American adult slept for 7.9 hours a night. Surveys now show that number is closer to 6.5 hours a night. To think that it has taken us millions of years to get a necessity of an 8 hour night in place, and then just 80 years later we drop it by over 17%.

The Brain During Sleep

During sleep, brain cells shrink by 60%, allowing the brain's glymphatic system to remove the waste. This is how the brain is restored during sleep, and you wake up refreshed and with a clear mind.

The brain stem controls all of the automatic processes that you don't think about. When you're holding your phone, that is the top part of your brain making that decision but while you're doing that, you are not thinking about your heart beat or how many breaths you are taking. Similarly, all the other processes that are automatic, circadian rhythm which is one of them, starts in the brain stem.

The Hypothalamus:

One of the main control centres that plays a crucial role in many important functions. For example when looking at Metabolic - appetite, cravings, metabolic rate, thyroid hormone release, cortisol, growth hormone, insulin sensitivity, leptin sensitivity and more.

It also controls:

• Thermoregulation

• Mood

• Wakefulness

• Sleep state

• Circadian rhythm

• Much more
  

Sleep for Learning - Dr Walker

Over the last 10 years, it has been discovered that people need sleep after learning in order to save the memories. REM sleep is the stage where your brain moves information from your short term memory to long term memory. It was recently discovered that your brain needs sleep before learning to prepare itself. Without sleep, the brain's memory log will struggle to absorb more memories.

A group of volunteers were assigned to one of the two experimental groups. One for sleep and one for sleep deprivation. The sleep group were getting a full 8 hours of sleep. The deprivation group were kept up in the laboratory, under full supervision with no naps or caffeine.

The following day, the volunteers were placed in an MRI scanner. They were given a list of facts to learn as the MRI was taking snapshots of brain activity. Following the scan, they were tested to see just how effective their learning has been. When the two groups were put head to head, it found a significant 40% deficit in the ability of the brain to make new memories without sleep. This can be concerning with the current education population as 40% could be the difference between acing an exam or failing it miserably.

The Hippocampus is a small, curved formation in the brain that is involved in the formation of new memories and is also associated with learning and emotions. Looking at the structure of those who had a full night of sleep, there was a lot of healthy learning related activity. When looking at the group who were sleep deprived, there was no significant signal whatsoever.

There was a recent push in the UK about starting teenage education at 10am to suit their natural biology, as I mentioned above about their chronotype. It's found that children from all ages, 5-18 years old, are having 2 hours less sleep than they were 100 years ago.

Another study was done in Minnesota in the US. It was to delay their school start times from 0725 to 0830, so that the children can sleep longer. To be at school by 0725 would mean that some school buses would have to leave at 0530, which would mean having some children wake up before 0500. This is ridiculous for kids to wake up at this time.

The study was to look at the results of their SATs (Standard Assessment Tests). In the year before making the time change, when the kids were going to school at 0725, the average SAT score was 1288. The following year when they were waking up later and starting school at 0830 had an average SAT score of 1500. That is a 212 point increase.

Ageing and Dementia:

It's no secret that as we get older, our learning and memory abilities begin to fade and decline. Deep quality sleep gets worse the older we get. Recent published evidence shows that having worse memories and worse sleep is not just co-occurring, they are in fact interrelated. The studies suggest that the disruption of deep sleep contributes to memory decline in ageing and Alzheimer's. Check out my article Sleep: Ageing and Parkinson's

Sleep and Immune Health

Natural Killer Cells locate dangerous elements and kill them. If we don't sleep enough then the numbers of our Natural Killer Cells drop.

An experiment was done with people having their sleep restricted for just 4 hours on a single night. It was then looked at to see the percentage reduction in immune cell activity. There was a huge 70% drop in Natural Killer Cell activity. This is why links are being found between short sleep duration and the risk of numerous forms of cancer. Currently the list includes cancer of the bowel, cancer of the prostate and cancer of the breast.

The link between lack of sleep and cancer is so strong that the World Health Organisation has clarified any form of night time shift work as a probable cause of cancer, due to a disruption of sleep wave rhythm.

Beauty Sleep is Real

A study was done at a sleep lab in Sweden to investigate whether sleep deprived people are perceived as less attractive and less healthy after a normal night’s sleep.

23 adults (aged 18-31) were photographed after a normal night’s sleep (8 hours) and after sleep deprivation (31 hours of wakefulness after a night of reduced sleep). The photographs were then presented in a randomised order and rated by 65 untrained observers (age 18-61). These observers were unaware of the sleep deprivation.

Sleep deprived people were rated as both less healthy and less attractive. This suggests that humans are sensitive to sleep related facial expressions, with implications for social and clinical judgments and behaviour.

Sleep for Fat Loss and Muscle Maintenance

"Sleep Loss Limits Fat Loss" - Dr Penev

A study was performed by Dr Plamen Penev from the University of Chicago, where 10 volunteers took on 28 days of monitored sleep.

The 10 volunteers were between the age of 35-50 with a BMI ranging from 25 (overweight) to 32 (obese). They were placed on an individual diet, with calories restricted to 90% of what their body needed to maintain his/her weight without exercise. The average amount of calories they consumed was about 1,450 per day, and was kept the same for the 28 days. They spent their waking hours engaging in home - or office like work or leisure activities.

Phase 1:

The first 14 days they had 8.5 hours in bed with an average of 7.25 hours sleep. They lost on average 3.1lbs of fat and 3.3lbs of muscle - Bearing in mind they were not exercising so didn't have much of a reason to keep the fat free mass.

Phase 2:

The last 14 days of the study, they had 5.5 hours in bed with an average of 5.2 hours sleep. They lost an average of 1.3lbs of fat and 5.3lbs of fat free mass

Getting adequate sleep also helped control the dieters hunger. Average levels of ghrelin did not change when dieters spent 8.5 hours in bed. When they spent 5.5 hours in bed, their ghrelin levels rose dramatically. Higher ghrelin levels reduce energy expenditure, stimulate hunger and food intake, promote retention of fat, and increase hepatic glucose production to support the availability of fuel to glucose dependant tissues.

Sleep for Athletes

• Roger Federer claims to sleep around 12 hours. 10 hours at night and 2 hours during the day.

• LeBron James has 12 hours sleep.

• Usain Bolt slept 9.5 hours and had naps strategically during the day. One of his world records, he had only been awake for 35 minutes before.

This isn't to say all athletes need this much sleep but they certainly need more than someone living an inactive life. When athletes start to shorten their sleep it has negative effects on their performance. If they sleep 6.5 hours or less, their time to physical exhaustion is dropped by 30%. For instance, if they are training for a 10km run but have a bad sleep, then they are more likely to get exhausted by 7km instead of 10km. Their peak muscle strength will decrease, their ability to exhale carbon dioxide will decrease, and the ability for their lungs to inhale oxygen will decrease.

The less sleep they have, the higher their injury list. When athletes sleep 6 hours or less, they had 80% chance of getting injured. If they were sleeping 9 hours a night, they were only 15-20% injury risk.

Kobe Bryant - "I used to sleep with my basketball":

Even if you are not a fan of basketball, I think everyone knows who Kobe is after his devastating death in 2020. Kobe made it very clear that his success in basketball increased dramatically after improving his sleep.

Once upon a time, Kobe said that he doesn't need sleep. Further into his career he realised that he was wrong. "I used to get by on three or four hours a night. I have a hard time shutting off my brain. But I've evolved. I'm up to eight hours now."

How Caffeine Affects Sleep

Caffeine is a class of drug called a Psychoactive Stimulant. It's one of the only stimulants that we regularly give to our children, without too much concern or thought. Caffeine can impact your sleep in a number of different ways. Because it is a stimulant, it is more likely that you will have difficulty either falling asleep, or staying asleep.

The duration of action is much longer than what most people would expect. Caffeine has a half life of 6 hours, but a quarter life of 12 hours. This means that if you have a coffee at 12pm then a quarter of that coffee is still in your brain at 12am. This will also result in your deep sleep being blocked.

Studies show that having anything between 150-200mg of caffeine in the evening can reduce your deep sleep by 20%. To put this into context, a 20% decrease in deep sleep is equivalent to you ageing 15-20 years from now.

Caffeine can be used strategically in the morning by cutting it down 14 hours before bedtime. Perhaps try decaffeinated coffee after 10am.

Daylight Savings Time - Cardiovascular, Depression and Accidents

Daylight savings time is when we set the clocks forward one hour in spring, and back again in the autumn, in order to make better use of natural daylight. Here are some reasons to end DST.

Cardiovascular:

A global experiment is done twice a year, using the medical records of 1.6 billion people in 70 countries.

In the Spring, when we lose just 1 hour of sleep, there is a 24% increase in heart attacks the following day. It decreases over time for up to 3 weeks.

In the Autumn, when we gain an hour of sleep, there is a 21% decrease in heart attacks the following day.

Now just think for a second, imagine those 1.6 billion people all slept an average of 7 hours a night. If they then dropped 1 hour of sleep and had a 24% increase that day, then they have an extra 1 hour of sleep with a 21% decrease the following day, that 2 hour difference could drop the percentage of heart attacks by up to 45%.

Depression:

Setting the clocks back and losing an hour of afternoon daylight can trigger mental illness, including bipolar disorder, and seasonal affective disorder (SAD), also known as winter depression.

• A Danish study found an 11% increase in depression cases after the time change. The cases gradually decreased over 10 weeks.

• An Australian study found that male suicide rates increased the day after the spring DST.

• Facebook found that more people were saying they were “tired” than on a normal Monday.

There are some simple ways of making it easier to handle the clock change:

• Adjust your body clock by progressively going to bed earlier and waking up earlier the week before. This makes it easier to get out of bed on Monday morning.

• Eat breakfast a little earlier than usual.

• Go for a walk in the light.

Accidents:

Major disasters, such as the nuclear accident in Chernobyl (1986), the Exxon Valdez oil spill (1989), Three Mile Island near-meltdown (1979), and the destruction of the Challenger space shuttle (1986), have all been linked to deprived sleep and/or disrupted circadian rhythms of involved supervisors or staff.

It's crazy to think that a bad night sleep destroyed a city and caused the evacuation of 50,000 citizens. I think that's a good excuse to jump into bed for an early night.

Studies also show:

• Tiredness caused by the clock change is thought to be the main cause for the increase in traffic accidents on the Monday following the start of DST. Scientists now believe sleep is a bigger killer than drugs and alcohol when it comes to traffic accidents.

• On the Mondays after the start of DST there were more workplace injuries. These injuries were also more severe compared to other Mondays.

• The start of DST has also been linked to miscarriages for in vitro fertilisation patients.

Depression Sleep problems that are associated with depression include insomnia, hypersomnia, and obstructive sleep apnoea. Insomnia is the most common and is estimated to occur in about 75% of patients with depression. It is then estimated that 20% of people with depression have obstructive sleep apnoea and 15% have hypersomnia. The majority of people with depression may alternate between insomnia and hypersomnia during one period of depression.

Sleep disruptions can affect the body’s stress system and disrupt circadian rhythms, making you more vulnerable to depression. Fortunately, people who are treated for major depression often report that their quality of sleep has increased. Overall, having healthy sleep reduces the risk of initially developing depression and the risk of relapse in people who have successfully been treated for depression.

I attended a seminar a few years ago, where I met Olympic Team GB Psychologist, Katie Warriner. She said about exercising your brain just as much as your body in order to keep it healthy.

"Did you know we have approximately 150,000 thoughts per day? Before you sleep tonight, think about 3 things you are grateful for or 3 things you did well. It's been shown to be as effective at changing our mood as taking antidepressants." - Katie Warriner

Sexual Health Info

Research studies have found multiple ways that nightly sleep can affect sex.

Men:

• A lack of sleep and disrupted sleep have been linked to a higher risk of erectile dysfunction.

• Men who sleep 5 hours or less in the night have significantly smaller testicles than those who sleep 7 hours or more.

• Men who routinely sleep 4-5 hours a night will have a level of testosterone of someone 10 years older. This means a lack of sleep will age a man by a decade in terms of that aspect of wellness.

Women:

There are equivalent impairments in female reproductive health caused by a lack of sleep.

Female Fertility

Research between fertility and sleep shows that women getting less than 7 hours of sleep are 15% less likely to get pregnant than women who got 7-8 hours. It's also been found that women who suffer from insomnia are four times more likely to struggle with fertility compared to women who are well rested.

Pharmaceutical Sleep

People often confuse having a racing mind with having bad sleep. Maybe they are anxious about something and they think that is the main cause of the bad sleep, so they think their solution would be to take sleeping tablets. However, that is the worst possible thing to do because they have just ignored the problem which is in the brainstem and hypothalamus and sedated their brain. They will get sleep but it will be terrible, and when they wake up the following day, they will repeat the same problems.

Pharmaceutical sleep and natural sleep are two different things as sedation is not sleep. Benzodiazepines such as: Restoril, Xanax, Valium and other historic sleeping pills literally obliterate stage 3 and 4 of sleep and almost knock it out completely. Sleeping pills are associated with Alzheimer's, cancer and death.

Alcohol:

A largely misunderstood "sleep aid". Alcohol is a class of sedative drug. It will knock out the cortex in the brain, sedating you and making you unconscious, but without going into naturalistic sleep. You will also wake up numerous times throughout the night. It also decreases the amount REM sleep you have that night.

Fix your Sleep Naturally

1. Regularity No matter whether it is the weekday or the weekend, go to bed at the same time and wake up at the same time. This will improve quality and quantity.
   

2. Temperature Dropping your body temperature by about 1°c will help you to initiate sleep and stay asleep. That is why it is easier to fall asleep in a room that is too cold than too hot. Aim for a bedroom temperature of around 18°c. If you are someone with a thyroid disease, 15.5-19°c might be better as hypothyroidism can decrease your tolerance to the cold. Having a bath or shower before bed can also help with body temperature. Although you would think that it would be making you hotter, it is in fact doing the opposite. Your blood rushes to the surface but when you get out of the bath, the heat radiates out of your body so that your core temperature decreases.
   

3. Light Exposure Blue light, which is part of the spectrum of sunlight, is 450-480 nanometres. It hits a cell in the eye called the Melanopsin cell, which turns off the Melatonin Phosphate in your brain. On the positive side, that is a great way to help wake you up in the morning. However, If you have terrible night's sleep, and you wake up in the morning for work and it is still dark, the Melatonin Phosphate is still on. A study had people reading on an iPad for 1 hour before bed, and people doing the same with a book. The iPad delayed the release of the Melatonin by up to 3 hours and reduced it by 50%. Smart phones have a setting where you can schedule the blue light. I set mine to turn off 2.5 hours before my average bed time, and turn back on in the morning 15 minutes after I wake up. There are also light bulbs and glasses which are made with a filter inside them to filter out the blue light.
   

4. Don't Stay Awake In Bed Do not stay in bed if you are awake. Your brain will learn the association of your bedroom being about wakefulness. Get out of bed and go to a different room. Keep the lights dim and participate in something peaceful and calming, such as reading a book.
   

5. Food The advice is simple; Don't go to bed too full, or too hungry.
   

6. Caffeine I talked about caffeine in more detail further up. Basic advice would be no caffeine after midday.

Supplements

Always talk to your doctor before you begin taking a supplement or make any changes to your existing medication.

1. Melatonin If you have circadian rhythm disturbances, then know that melatonin is a circadian rhythm regulator. It also controls the production of other hormones, helps regulate the body’s internal temperature, and influences cognitive performance and mood. It's a naturally produced hormone that is released by the pineal gland at night, but is also available in supplement form. Here in the UK it has to be prescribed, but can be sold over the counter in the US. Two separate benefits of melatonin are that It is a potent fighter against the growth and spread of cancer cells and prevents the formation of two proteins that are key biological markers of Alzheimer’s disease. Melatonin is not suitable for long term use for women who are still fertile, as it is possible for it to suppress fertility.
   

2. Magnesium Magnesium deficiency is common for adults. It is an essential mineral that your body needs in high quantities. People with low magnesium often experience restless sleep and waking frequently throughout the night. Insomnia is a common symptom of magnesium deficiencies. Maintaining healthy magnesium levels often leads to deeper and better sleep. Because it is not produced in your system, you need to find it in foods and/or supplements. Here are some magnesium rich foods:

• Nuts

• Meat

• Dairy products

• Broccoli and leafy greens

• Whole grains

• Chocolate Supplemental magnesium is also quick and effective. It has been shown to have a stabilising effect on mood. It is effective in relieving symptoms of moderate anxiety and moderate depression.

Fixing Insomnia with Cognitive Behavioural Therapy (CBT)

Our inability to slow down due to stress is a cause of Insomnia. It is not a surrounding problem such as light exposure. It is usually a problem with something going on in their life. CBT - Cognitive Behavioural Therapy is highly effective to help improve mental health with development of personal coping strategies.

The physical stage of the therapy is to schedule the sleep with restrictions. If they usually go to bed at 2300 but don't get to sleep until 0100 then instead they will be scheduled to go to bed at 0100 instead. Building up the natural sleep deprivation on purpose will help to fall asleep and stay asleep.

The mental stage of the therapy is to ask them questions about their sleep, followed by giving them facts. Educating people on the positive effects of sleep and negative effects of sleep deprivation.

Similar Articles

Sleep: Ageing and Parkinson's

Sleep: Underactive & Overactive Thyroid

Source & Reference

15-20 sleep studies come out each month. That's between 180-240 studies a year.

1. Dr Plamen Penev - University of Chicago. Senior Medical Director at Covance Research. More than 20 years experience in clinical research for Diabetes, Obesity and Cardiovascular disease.
   

2. Dr Michael Breus (@thesleepdoctor) - Clinical Psychologist and Diplomat of the American Board of Sleep Medicine and also the Academy of Sleep Medicine. Specialises in Sleep Disorders with more than 15 years experience.
   

3. Dr Matthew Walker - PhD in Neurophysiology from the Medical Research Council in London. Professor of Psychiatry at Harvard Medical School. Director of the Centre for Human Sleep Science. Over 100 published scientific research studies.
   

4. Dr Jason Mckeown - CEO of Neurovalens Medical Devices. Associate of British Neurologists, currently a Visiting Scholar at the University of California's Center for Brain & Cognition.
   

5. Katie Warriner - Olympic Team GB Psychologist