We spend around a third of our lives asleep. Sleep is as essential to our bodies as eating and drinking and is vital for ensuring good physical and mental health.

However, a study has found that a lack of sleep costs the UK economy as much as £40 billion a year in lost productivity. Rand Europe analysed survey data from 62,000 people in five countries and found that employees who sleep for less than six hours a night lose around six more working days through absenteeism or presenteeism each year than those who sleep seven to nine hours a night.

Sleeping less than seven hours a day also leads to a higher mortality risk and lower productivity levels through a combination of absenteeism and employees not working to their full capacity. The losses stemming from this cost the UK 1.86% of its total GDP.

So, why is sleep so important? Keep reading to find out, and for tips on getting a better night’s sleep.

Sleep makes you more productive

Several studies in the 2000s looked at the effects of sleep deprivation. Researchers concluded that sleep has links to several brain functions including:

• Productivity
• Cognition
• Concentration

A more recent 2015 study in the Journal of Child Psychology and Psychiatry showed that children’s sleep patterns can have a direct impact on their academic performance.

So, good sleep can make you more productive and improve your concentration levels.

You can lower the risk of heart disease

High blood pressure is one of the major risk factors for heart disease. And, according to the American Centre for Disease Control and Prevention, getting enough sleep each night allows your body’s blood pressure to regulate itself.

It is believed that sleep helps your blood regulate stress hormones and helps your nervous system to remain healthy. Over time, a lack of sleep could hurt your body’s ability to regulate stress hormones, leading to high blood pressure.

You can reduce the risk of an accident

Sleep deprivation can reduce your reaction speed as much as a blood alcohol level of 0.08g – the legal limit for driving.

Sleepiness reduces reaction time; a critical element of safe driving. It also reduces alertness and concentration so that the ability to perform attention-based activities (such as driving) is impaired.

RoSPA reports research that shows driver fatigue may be a contributory factor in up to 20% of road accidents, and up to one-quarter of fatal and serious accidents.

You can control your weight

There is a growing body of research which suggests there is a link between how much people sleep and how much they weigh. In general, children and adults who get too little sleep tend to weigh more than those who get enough sleep.

For example, in a Nurses’ Health Study, researchers followed roughly 60,000 women for 16 years, asking them about their weight, sleep habits, diet, and other aspects of their lifestyle.

At the start of the study, all the women were healthy, and none were obese. 16 years later, women who slept five hours or less per night had a 15% higher risk of becoming obese, compared to women who slept seven hours per night.

Short sleepers also had a 30% higher risk of gaining 30 pounds over the course of the study, compared to women who got seven hours of sleep per night.

How to make sure you get enough sleep

According to the Sleep Council, the recommended amount of sleep adults should have depends on your age:

• 12 – 18 years old: 8 to 9 hours per day
• 18 – 65 years old: 7 to 9 hours per day
• 65+ years old: 7 to 8 hours per day

If you’re not getting the right amount of sleep your health could suffer (as outlined above). However, there are steps that you can take to improve your sleep habits:

• Make enough time for sleep – many people squeeze sleep out of their schedule, but actually ensuring you have enough time to sleep can help.
• Keep a sleep routine – if you can, go to bed and wake up at the same time every day, including weekends. Staying up late and sleeping in late on weekends can disrupt your body clock’s sleep/wake rhythm.
• Restrict screen time in the evening – experts suggest that you don’t look at a computer or phone screen for 1-2 hours before bedtime as the light may signal to your brain that it’s time to be awake. If you do need to use your phone, then consider installing a blue light filter on your device.
• Avoid caffeine and nicotine before bed – both are stimulants and can interfere with your sleep. Sleep expert Kathryn Pinkman suggests avoiding caffeine after 4pm as the effects can last as long as eight hours.
• Consider a nap – napping during the day can give you a boost in alertness and performance. Take naps earlier in the day and try not to let them exceed 20 minutes.
• Create a good environment for sleep – keep your bedroom quiet, cool and dark. Make sure your room is uncluttered, you have a comfy mattress, and even consider earplugs for snoring partners or noisy neighbours.
• Wind down as you approach bedtime – a warm bath can help your body reach an ideal resting temperature and light relaxation stretches can help to relax your muscles. Reading a book and writing ‘to do’ lists for the following day can both organise your thoughts and clear your mind.

Although it’s important to be mindful of these things, they “will improve sleep but the reality is that they are not cures for a sleep problem”, expert Kathryn Pinkman adds.

If you obey the strictest sleep hygiene but still sleep poorly, it could be that “you’re thinking too much about it and doing too many things to try and make it work”.