The importance of sleep for a healthy lifestyle

Sleep is one of our basic human needs, and so ensuring we get enough of it is essential for our health and well-being. In this blog we will explore how poor sleep affects our health, and share some top tips to help you improve the quality of your sleep.

Understanding sleep

As sleep is a fundamental need for the body, it affects emotional well-being, cognitive function, daytime performance and physical health. Poor sleep quality can influence weight and appetite and has been associated with obesity, diabetes, hypertension and cardiovascular disease risk in many studies.1

The recommended duration of sleep varies across the lifespan. For most adults, 7-9 hours is thought to be optimal, whereas a child can require between 8-15 hours of sleep per day.2

Several lifestyle factors can contribute to poor sleep quality. The top culprits include caffeine and alcohol consumption, diet, electronic media exposure, bright lights during night hours, stress, shift work and timing of sleep.

How does poor sleep affect our health?

Immunity

A lack of sleep can weaken the immune system and increase susceptibility to infections such as the common cold.3  One study highlighted how inadequate sleep can trigger an immune system response in the body, increasing inflammation and causing tissue damage. This helps us to further understand the link between sleep problems and increased risks for diseases like diabetes, arthritis, heart disease, obesity and some cancers.4

Diabetes

Poor sleep has been associated with reduced postprandial (post-meal) insulin secretion and increased secretion of the stress hormone cortisol. Cortisol can worsen sleep and reduce the effectiveness of insulin leading to raised blood glucose levels and increased risk of developing Type 2 Diabetes.5

Obesity

There is a complex relationship between inadequate sleep and obesity. Lack of sleep can affect appetite controlling hormones and pleasure systems in the brain, leading to poor food choices, overeating and weight gain. Additionally, fatigue reduces engagement in physical activity which can drive further weight gain.

Although further research is required, some studies associated poor sleep with decreased levels of the satiety hormone leptin and increased levels of the appetite-stimulating hormone ghrelin, leading to increased hunger and food intake.5

Mental well-being

Poor sleep and mental well-being have a converse relationship. Worry, stress and anxiety disrupts sleep. Whereas, poor sleep can lead to anxiety disorders and exacerbates stress. It’s a vicious cycle.

Seasonal affective disorder (SAD) can cause oversleeping or irregular sleeping patterns. This can increase risk of isolation, loneliness and depression if missing out on socialisation.

Post-traumatic stress disorder (PTSD) can cause nightmares and night terrors which disturbs sleep.6

Tips for improving sleep

Limit alcohol consumption

Alcohol interrupts the circadian rhythm, can suppress the REM stage of sleep, which is the stage where memories are consolidated, and decreases overall sleep quality.7 Alcohol is also a diuretic, leading to frequent toilet trips, again decreasing sleep quality.

• Avoid alcohol a few hours before bed.
• Aim to reduce alcohol consumption.
• The government guidelines recommend limiting to 14 units of alcohol spread over 3 or more days of the week.8

Create an optimal environment

How to create an environment which is conducive to a good night’s sleep.

• Temperature: 16-18°C is thought to be optimal.9
• Choose a heavy or light duvet depending on the season.
• Set your heating on a timer or leave a window slightly open to help maintain optimal temperature.
• Reduce noise: Try earplugs to block out any background noise.
• Light: Try a sleep mask or blackout curtains to make the room darker.
• Comfort: Invest in a quality mattress and pillows or mattress topper.

Exercise

Exercise is important for health and well-being. Many studies have shown that exercise improves sleep quality. People who exercise regularly report better sleep quality than those who don’t exercise.10

• Exercise increases heart rate and body temperature which promotes the release of adrenaline and endorphins. This helps to relieve stress and anxiety, keep us alert and productive, and make us happier.
• As exercise uses energy, it increases your body’s desire to sleep at night, helping you fall asleep easier at night.

Some tips to exercise in a way that helps you sleep include:

• Try to keep high-intensity activity to daytime or early evening, and ensure your workout finishes at least an hour before you go to bed. This is because the increase in heart rate, body temperature and adrenaline before bed can worsen sleep.
• If exercising close to bedtime, try a calming activity such as yoga.

Food and drink

Certain food and drink, when eaten before bed, can hinder sleep.

• Spicy, high fat meals before bed can cause indigestion and acid reflux.
• Diuretic foods (such as watermelon and celery) and drinks (for example, dandelion tea, alcohol, coffee) can cause frequent toilet trips which disrupts sleep.
• Caffeine is a natural stimulant. It takes approximately 6 hours for half the caffeine consumed to be removed from the body. Try avoiding caffeinated products (eg: coffee, chocolate, energy drinks) after midday.

A light snack, rich in sleep promoting nutrients is recommended if hungry before bed, for example:

• A bowl of low-sugar cereal and milk.
• Cheese and oatcakes.
• Peanut butter on wholemeal toast.

Reduce stimuli

Modern technology such as phones, computers and TVs release ‘blue light’ which affects the circadian rhythm by suppressing melatonin production.

• Remove TVs and phones from the bedroom to create a relaxing environment.
• Limit use of these devices two hours before bed.
• Reduce blue light by using the ‘blue light filter’ on devices or invest in a pair of ‘blue light’ glasses to wear 2 hours before bedtime.

Routine

A bedtime schedule, and choosing a similar time to go to bed each night and to wake up each morning2, can regulate circadian rhythm promoting a quality sleep.

Engage in a relaxing routine to help prepare for sleep:

• A relaxing bath with Epsom salts (these are rich in magnesium).
• Lavender scented candles/oils have calming effects.
• Listen to soothing music or read a book.
• Meditation supports stress reduction12. Apps such as ‘Headspace’, ‘Calm’, ‘Buddhify’ can be a useful guide.
• A warm camomile tea or milky drink.

Shift workers

Irregular schedules, altered lighting and sleeping out of sync with people around interferes with the body’s circadian rhythm.

• Request a block of shifts to establish some routine.
• Prepare for a night shift by rising 2 hours later and going to bed 2 hours later. Most people cope with 2-3 hour shifts in their sleep-wake cycle.
• Eat meals at the same time each day to promote regular body cycles.
• Napping before a shift can reduce sleepiness at work.
• Limit stimulants such as caffeine to the first half of a shift to minimise the effect on sleep after work.
• Seek out bright light during the early part of a night shift to help stay alert.