The sleep we get before midnight is called the 90 minute phase – and it's one of the most important and restorative phases of sleep, but how can we improve our nightly routine to ensure we drift off?
And while we may have found our way back to a solid seven or eight hours, they might not be the seven or eight hours our body needs to be at its best.
Why? Because the hours of sleep we manage to shoehorn in before midnight are the most restorative we can get.
This pre-midnight phase is called the 90 minute phase (as in, the hour and a half we should aim to get before the clock strikes 12) and it allows the brain to reorganise itself and reduce adrenaline levels. Which, in unprecedentedly stressful and anxious times, is an important step in the journey to a decent night's slumber.
“The 90 minute phase before midnight is one of the most powerful phases of sleep, because it’s the period where the body is replenished,” Dr Nerina Ramlakhan, author of Tired But Wired: The Essential Sleep Toolkit, told Stylist.“It’s rejuvenated on every level – physically, mentally, emotionally and, I believe, spiritually as well. There’s a lot of healing that takes place in that first phase of sleep.
“It’s also a really important phase for reorganising the brain," she said. "So all the information we’re taking in during the day gets reorganised during that phase of sleep before midnight, and it’s very important for bringing adrenaline levels down – if you’re under a lot of stress, you want to make sure you get that phase before midnight.”
Plus, most of us are ready for some shut eye well before midnight; so it's important we pay attention to our circadian rhythm, and let the body take its natural course.
What is circadian rhythm?
Your circadian rhythm is the 24-hour cycle that occurs in the physiological processes of living things. It's not just humans who are attuned to them – plants, animals and fungi also have them. Circadian rhythms exist in every cell in the body and help to set sleep patterns by dictating the flow of hormones and other biological processes.
They're controlled by the body's internal clock and influenced by environmental factors such as light and temperature – which is why your body knows it's time to sleep when it's dark, and time to wake with the light.
How much sleep should we aim to get?
While the seven to eight hour adage is a useful guideline, the amount of sleep each of us needs is totally individual. And most of the time, it's about quality over quantity.
It's recommended that around 75 per cent should be non-Rapid Eye Movement sleep (the start of the sleep cycle), and 25 per cent REM (this is usually the phase when you dream).
While new research suggests that seven is actually the optimum number of sleep time as oppose to the conventionally heralded eight, a study by The American Academy of Sleep Medicine concluded that those who consistently got less than seven hours of shut eye were more at risk of hypertension, diabetes, stroke and other cardiovascular and metabolic disorders.