Sleep is one of the few essentials your body can’t do without. During shut-eye, millions of your cells rest and renew themselves. Your body also produces more of a natural chemical called interleukin-1, which is responsible for organising the immune system. With less sleep and lower interleukin-1 levels, you could become more susceptible to disease.

Studies suggest that in the long term, sleep loss weakens willpower, causing individuals to skip the gym and eat more. Ghrelin, a hormone that stimulates appetite, is increased due to sleep deprivation, while mental alertness, judgement and reflexes all diminish. Research also shows that going 24 hours without sleep leads to reduced hand-eye co-ordination similar to that experienced with a blood alcohol level of 0.1. Yet, though most of us say we wish we enjoyed more sleep, most Australians are clocking up less than seven hours a night.

Nod knowhow

A University of California study involving more than 1 million people found that those who sleep more than eight hours a night die younger, though it’s not yet clear why. That doesn’t mean you should be unconcerned about burning the midnight oil: studies at the University of Chicago have found that sleeping less than six hours a night causes a 40 per cent drop in sensitivity to insulin. This, in turn, increases the risk of developing weight gain, obesity, high blood pressure and type 2 diabetes — all conditions that can shorten your lifespan.

So how much sleep should you be getting? The optimal amount is 7–8 hours, even in later life (though you might find from your 60s on that you feel sleepier earlier in the evening and wake earlier in the morning).

If sleep is a constant problem, don’t ignore it. The longer sleep difficulties go on, the more your body’s rhythm resets its meter. Ongoing insomnia, for example, can cause the suprachiasmatic nucleus, which lies at the base of the brain, to trigger sleepiness at the wrong times, so, although you can barely keep your eyes open at lunchtime, you might find yourself so energised that you have trouble getting to sleep after midnight.

Sleep hygiene

Struggling to get out of bed each morning? The answer could lie in paying attention to your sleep rituals and environment. Good sleep hygiene involves creating a peaceful environment and adhering to a sleep routine. Adopt the following snoozy strategies to help you avoid wakeful nights:

• Become a creature of habit: As much as possible, aim to rise and retire at the same time every day (and avoid a siesta if you had a late night). A predictable sleep routine helps synchronise your body’s circadian rhythm to light and dark. This ensures that at sleep time your body temperature is dropping (making it easier to fall asleep) and rising again at the right time in the morning (when you need energy to face the day). Avoid exercising two hours before bedtime as this will elevate your body temperature when you want it to drop.
• Set a meal curfew: Don’t eat a meal later than 8pm or you will kick-start your metabolism, which might keep you awake later. Before bed, enjoy a tea of nervine herbs such as chamomile, lemon balm or skullcap, which act as calmatives. Or drink a hot cup of milk with honey as this contains tryptophan, an amino acid that helps your body produce a natural relaxant called serotonin.
• Avoid mother’s little helpers: Although a few glasses of wine might help you drop off to sleep, alcohol causes rebound wakefulness later. Think twice before reaching for sleeping tablets, too. They may help you fast-track to sleep, but they could end up creating problem such as depression, daytime drowsiness and withdrawal symptoms from addiction. For a healthier sleep-inducer, try valerian tablets. Or slip on light cotton socks for 10 minutes. Swiss research has shown warming the feet before bed dilates blood vessels, which promotes faster sleep onset.
• Chill out: Some health practitioners recommend Knapp’s cold cure, which involves briefly applying cold water packs to the back of the head, without drying, just before you’re ready to turn in for the night. This slows blood circulation to the brain and may help put your mind into go-slow mode at the same time.
• Put down that book: Avoid activities such as reading or checking emails on your laptop in bed as these stimulate wakefulness (research now shows that light from the screen interferes with sleep hormones and sleep onset). Can’t sleep? After 15–20 minutes, relocate to the lounge room and listen to music by lamplight or candlelight until you start to feel drowsy. Don’t turn on bright lights.
• Banish sleep thieves: To promote rest, your bedroom needs to be sleep-friendly. Turn your alarm clock so you can’t see the time, put pets in the laundry so they can’t scratch at your door and banish snoring partners. Wear a sleep mask and earplugs to enhance sleep quality and, if necessary, install new curtains to make sure your room is dark.
• Turn off your mind: A pre-bed soak in a bath with mineral salts or botanical essences is an enjoyable way to relax tense muscles. Another good strategy is to sprinkle essential oils on your pillow. Try ylang ylang, lavender, clarysage, rosemary, basil or neroli, which are all good for promoting calmness and serenity.
• When you go to bed, try this relaxation ritual: Systematically tense and release all muscles, engage in rhythmic breathing and visualise appealing scenes such as a Japanese garden.

These strategies may not send you to sleep immediately but will put you in the mood for rest. Incorporate them into your bedtime habits and they will sustain a legacy of health benefits to boost your wellbeing both day and night.