How Lack Of Sleep Affects Health

Sleep is the time for repairing damaged cells and tissues as well as creating new cells in our bodies. It’s also crucial for maintaining our mental health and reducing stress.

Adults should ideally sleep for 7 to 9 hours per night but it’s estimated that a staggering 50% of us aren’t getting enough sleep. Other than just feeling sleepy and grumpy the following day, there is substantial evidence to show that regularly sleeping less than 7 hours a night has wide-ranging negative effects on our health. 

The main reasons for poor sleep can fall under three, often overlapping categories. 

1. Lifestyle

This relates to factors like working very long hours, doing shift work, staying awake too late looking at screens, using stimulants like caffeine too late in the day, drinking alcohol before bed time. What has also become a worrying trend is that people are sleeping less to get more work accomplished and are staying up later to watch programs or use the Internet. This hasn’t been helped by the work from home model where it’s harder to keep work and home life separate. 

2. Mental Health

Up to 80% of people who suffer from mental health conditions, will have some type of sleep disturbance. This ranges from those with depression and anxiety right through to people diagnosed with conditions like bipolar disorder and schizophrenia. When you consider that 1 in 4 people suffers from a diagnosable mental health condition, that’s a worryingly high percentage of people who are unable to get good quality sleep.

3. Sleep Disorders

The third category of those with poor sleep is that of diagnosed medical sleep disorders. The most common ones are sleep apnoea, narcolepsy and sleep movement disorders like restless leg syndrome. And it’s so important to remember that it’s not only the person with a sleep disorder who can’t get enough sleep, their problem has a major impact on the partner who sleeps beside them.  Research has shown that up to 7% of men and 5% of women suffer from sleep apnoea, and this number is on the rise with the growing rates obesity which is a major risk factor for sleep disorders. 

Sleeping well quite literally improves everything in our lives from lowering blood pressure, improving memory to increasing the body’s ability to burn fat. Here are some proven links between sleep and certain health problems. 

Overweight and Obesity

There is a wealth of evidence that people who sleep less tend to carry more weight and in turn people who carry more weight have more difficulty sleeping. A 13 year analysis of 500 people showed that by their late twenties, people who slept an average of 6 hours a night were 7.5 times more likely to be overweight!

We also know that chronic sleep deprivation affects our appetite hormones. In particular, the level of our hunger hormone ghrelin rises, and our satiety hormone leptin falls. So not sleeping enough leads to over-eating and weight gain. 

Pre-Diabetes and Type 2 Diabetes

Chronic sleep loss increases the risk of pre-diabetes and diabetes. In addition to the weight gain discussed above, lack of sleep creates a state of stress in the body leading to rising levels of cortisol, the stress hormone. Cortisol prepares the body for stress by trying to make energy more available, releasing glucose from the liver into the blood stream. But chronic poor sleep is not the same stress as the stress of fighting an infection or running from a predator. This glucose in the blood stream isn’t going to be used up just from tossing and turning in bed, or flicking between tv channels at 2am. Sleep loss is a double-edged sword in this case because it also affects the pancreas, suppressing the release of insulin. So, this glucose in the blood stream has nowhere to go, overtime increasing the risk of developing type 2 diabetes. A landmark study showed that just a single night of partial sleep deprivation induces insulin resistance, a prediabetes state, even in healthy people! The Sleep Heart Health Study which followed over 6000 participants, showed that adults who slept 5 hours or less a night had a 2.5 times increased risk of developing diabetes!

Heart Disease

Sleep deprivation is a risk factor for heart disease because it leads to raised blood pressure and inflammation in the blood vessels which can contribute to the build-up of cholesterol in the arteries. If this build-up occurs in the plumbing system to the heart, the coronary arteries, it can lead to angina and heart attacks.  

Mental Illness

Whilst sleep loss is a common symptom of mental health conditions, chronic sleep loss can actually be the trigger for mental illness and emotional upset especially depression, anxiety, behaviour problems and alcohol overuse.  About a third of people struggling with insomnia say they use alcohol to help them sleep better. Research has shown that persistent sleep deprivation affects the release of pleasure-inducing neurotransmitter release in the brain.

Brain Function

Chronic poor sleep affects executive brain function, memory formation and decision making. We’ve all experienced this after just one night of poor sleep. Sleep is the time when memories are made as short-term memories are transferred into our long-term memory bank. If you can’t sleep properly, this system is weakened. Sleep deprivation also affects the way our brain cells communicate with one another, slowing down messages and giving the overall feeling of sluggishness or having a brain fog. Because of these changes it becomes much harder to perform complex tasks or make difficult decisions during a state of sleep deprivation. 

Other Health Risks

Infertility. Although it’s not yet clear how, sleep deprivation affects female and male fertility, making it harder to conceive.

Chronic pain. Sleep deprivation affects our pain threshold and can lead to aches and pains all over the body.

Auto- immune disease. The stressed and inflammatory state created by sleep loss is a trigger for developing diseases like lupus, rheumatoid arthritis and even thyroid disease.

Learn more about how to make good quality sleep a priority in your life here.

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