When it comes to improving health, many of us tend to focus our efforts on diet and exercise alone. And while these form some of the key building blocks of health, science has found that getting enough good-quality sleep is just as important.
Here, we’ll explore some of the impressive benefits of sleep and how a good nighttime routine is important for both health and overall quality of life.
Note: We understand that sleep can be a difficult and frustrating topic for some people. If you’re currently struggling to get enough good-quality sleep, you might find some of the sleeping tips in the sleep and fatigue section of our website useful. Alternatively, if you see no improvement in your sleep, it’s worth speaking to your GP.
10 surprising health benefits of sleep
1. It can improve focus and boost productivity
Sleep is important for healthy brain function. Among other things, sleep allows neurons and neurotransmitters in the brain to rest and regenerate. As a result, research has found that a lack of sleep can have a significant impact on things like focus, productivity, and performance at work.
People who’re sleep deprived are thought to be more likely to make mistakes due to slower reaction times, trouble concentrating, and greater vulnerability to stress.
For example, this study, which looked at overworked physicians, revealed that a lack of sleep significantly impacted their ability to focus and perform. It found that doctors who were moderately, highly, and severely sleep-deprived were 54%, 96%, and 97% more likely (respectively) to make significant medical mistakes.
Recent research has revealed that the impact of sleep deprivation on productivity is thought to cost the UK economy a staggering £37 billion each year.
In contrast, other studies suggest that getting enough good-quality sleep can improve memory and problem-solving skills in adults and lead to greater performance at work.
2. It can strengthen your immune system
The importance of sleep for healthy immune system function is well-documented.
One study found that participants who slept for less than five hours a night were 4.5 times more likely to develop a cold compared to those who slept for more than seven hours.
There’s also evidence to suggest that getting enough good-quality sleep may improve our antibody response to flu vaccines.
Plus, other recent studies on the Covid-19 vaccine have suggested that getting enough sleep before and after receiving the vaccine may improve its effectiveness. Though, more research is needed to confirm these findings.
3. It can boost heart health
According to research, a lack of good-quality sleep can increase your risk of developing heart disease.
For example, this scientific review found that there was a 13% increased risk of death from heart disease in people who slept for less than seven hours a night. Another analysis found that when compared with seven hours of sleep, every one-hour reduction in sleep increased the risk of heart disease by 6%.
One explanation for this is that sleep deprivation can contribute to raised blood pressure and cholesterol levels – two main indicators linked with the risk of heart disease.
Studies also suggest that short sleep may increase the risk of developing high blood pressure, particularly in people with obstructive sleep apnea (a condition that causes interrupted breathing during sleep). In fact, this study found that those who slept for fewer than five hours per night had a 61% higher risk of developing high blood pressure than people who slept for seven hours.
Similarly, research has shown that not getting enough sleep can lead to high levels of LDL (bad) cholesterol.
That being said, getting too much sleep (more than nine hours per night consistently) can also increase the risk of developing high cholesterol and high blood pressure – and therefore heart disease. So, aiming for between seven and nine hours of sleep per night is ideal.
4. It may help you to maintain or lose weight
A number of studies have linked a lack of sleep (defined as getting fewer than seven hours per night) with a higher risk of weight gain and a higher body mass index (BMI).
For example, this 2020 study found that adults who slept for less than seven hours a night were 41% more likely to develop obesity. Getting enough sleep, on the other hand, didn’t increase the risk of developing obesity at all.
Experts suggest that the link between sleep and weight gain is down to a number of factors, including hormone balance and motivation to stay active.
Not getting enough sleep causes an increase in ghrelin and a decrease in leptin. Ghrelin is the hormone responsible for signalling when we’re hungry, while leptin signals when we’re full. So, an imbalance can lead us to feel hungry and overeat.
These findings are supported by various studies, which have found that sleep-deprived people have a bigger appetite and a tendency to eat more calories.
A lack of sleep can also result in cravings for high-calorie foods to compensate for a lack of energy. And unsurprisingly, low energy levels can also make it more difficult to stay active.
5. It can improve the health and appearance of skin
Sleep is a time when the body repairs itself, and this is just as true for your skin as it is for your muscles or brain.
While we sleep, blood flow to the skin increases as it begins to rebuild its collagen content and repair skin cell damage from sun exposure.
Research shows that even just one night of poor sleep can cause dark under-eye circles, paler skin, and swollen eyes (and many of us will be able to vouch for that!). However, in the long term, sleep deprivation can also weaken the skin barrier and impact its ability to protect and repair itself.
For example, this study found that people who got enough good-quality sleep had 30% greater recovery for their skin barrier – the outer layer of skin that helps to protect the skin from external elements like UV rays – compared to people who slept poorly.
It also found that 24 hours after being exposed to UV light, those who got enough sleep recovered better from erythema (a type of skin rash caused by inflamed or injured blood capillaries).
6. It can improve emotional regulation and lead to strengthened relationships
A lack of sleep is thought to reduce our ability to regulate emotions and interact with others.
Many of us will relate to the experience of feeling sad, irritable, and less able to control emotional outbursts when we’re tired – and science has also confirmed this link.
As well as affecting our own mental well-being and happiness, these negative moods caused by a lack of sleep can impact our ability to interact with others.
Experts have also suggested that chronic sleep deprivation can increase the risk of loneliness because people are more likely to withdraw from other people and social events. And, these factors can have an impact on the quality of relationships too.
Take this study, for example, which found that couples who got better quality sleep were less likely to be emotionally reactive to one another; and more likely to feel secure in their relationships and stay together for longer.
7. It may reduce stress and anxiety
There’s also a significant link between sleep and levels of stress and anxiety.
A lack of sleep can cause the body to react as if it’s in distress – releasing more of the stress hormone, cortisol. For example, this study found that adults who sleep for less than eight hours a night reported higher stress levels than those who sleep for at least eight hours.
Cortisol is responsible for producing our fight-or-flight response to danger, but too much can harm our health. This study linked getting less than five hours of sleep a night to a number of cortisol-related issues, including high blood pressure.
Getting more rest, on the other hand, can restore balance to the body’s systems and significantly reduce cortisol (and therefore stress and anxiety) levels.
8. It can reduce your risk of developing type 2 diabetes
Science has associated a lack of sleep with an increased risk of developing type 2 diabetes.
For example, this scientific review of over one million participants found that sleeping for less than five hours and less than six hours increased a person’s risk of developing type 2 diabetes by 48% and 18%, respectively.
The increased risk is believed to be the result of physiological changes that sleep deprivation can cause in the body. This includes reduced insulin sensitivity (when the body is unable to use the hormone insulin properly), increased inflammation, imbalances in hunger hormone levels, and a greater likelihood of overeating – all of which are risk factors for diabetes.
Poor sleep can make other health conditions like obesity, metabolic syndrome, and heart disease more likely too. These conditions are also linked with an increased risk of diabetes.
9. It can improve your reaction times and reduce the risk of accidents
As mentioned earlier, when we’re sleep deprived, our focus, reflexes, and reaction times are all affected. In fact, research has found that severe sleep deprivation has a similar effect to excessive alcohol consumption.
This study found that people who slept for fewer than six hours a night were more likely to fall asleep while driving. Another study found that people who slept for fewer than four hours a night were 15.1 times more likely to have a car accident.
Other research has reported that staying awake for 17 hours or more is comparable to having a blood alcohol content (BAC) of 0.05% – increasing to 0.10% after 24 hours, which is above the UK limit of 0.08%.
There’s also evidence to suggest that a lack of sleep can increase the risk of injury in the workplace.
10. It can boost athletic performance
Getting enough, good-quality sleep has been shown to boost athletic performance.
This is largely due to the fact that the body’s production of growth hormones needed for muscle tissue repair and growth is highest during sleep.
This study found that when male and female tennis players improved their sleep, their serves became more accurate, from around 36% to 42%. Players also reported feeling less tired during exercise too.
Another study found that when male and female swimmers slept for longer, their turn times improved, kick strokes increased, and reaction times off diving blocks were quicker.
Athlete or not, when it comes to exercise, these benefits can be enjoyed by anyone – whether that means feeling more fuelled and ready for your workouts, or moving steadily towards your fitness goals.
Final thoughts…
Sleep is essential for health and well-being because it allows our bodies to rest and rejuvenate. While eating a balanced diet and exercising regularly are important steps to take when building a healthy lifestyle, the quality of our sleep should equally be considered too.
For more sleep-related content, head over to the sleep and fatigue section of our website. Here you’ll find information on everything from finding the ideal mattress for you, to how to create an environment for sleep and overcome insomnia.