The science of good sleep
Humans have long been concerned with sleep – how to get it, how much to get and what happens if we don’t get enough.
Yet, even now, research into sleep continues to unearth new – and somewhat startling – findings about the effects of a sub-optimal amount of shut eye.
English neuroscientist Dr Matthew Walker has spent the best part of two decades exploring the topic of sleep. As the Director of the Center for Human Sleep Science at the University of California, Berkeley, he spends his days (and we’re guessing some nights too) understanding why sleep matters and how to get more of it.
His results culminated in a ground-breaking book published in 2017 called Why We Sleep: The New Science of Sleep and Dreams.
In it, Walker proves how crucial sleep is to every aspect of our physical and mental wellbeing. From our ability to learn and retain information, our decision-making capability, emotional regulation, hormone and metabolism, immune health, to warding off diseases like dementia, quality sleep is linked deeply to how we get on during the day.
A lack of good quality consistent sleep can lead to an array of health problems. Short term, sleep deficit can lead to forgetfulness, impaired memory, lack of focus and emotional dysregulation. Long term, sleep deprivation can trigger insomnia and narcolepsy, heighten the risk of cancer and heart disease, lead to cardiovascular issues, and shorten overall lifespan.
Given what we now know about the importance of sleep for both short and long term health, it’s clear that “sleep is not an optional lifestyle luxury. It is, in fact, a non-negotiable biological necessity.”
Practical tips for more (and better) sleep
Of course, it’s one thing to know how important sleep is. But another entirely to actually get enough.
Here, Dr Walker elucidates on the critical importance of good sleep hygiene. That is, the habits, behaviours and environmental factors that influence how well you sleep.
A consistent sleep schedule is essential, he says. Avoid using weekend mornings to play catch-up on sleep lost during the week. This plays havoc with your circadian rhythm, making it harder to fall asleep and leading to further sleep disturbances.
Avoid screens in the lead up to bed, opting instead for a calming activity such as reading, listening to music, meditating or journaling.
Lighting should also be turned down to simulate sunset conditions. Opt for warm light bulbs during the evening, turning off overhead lights wherever possible.
Creating an optimal sleep environment is also essential. Cool – around 18 degrees Celsius – and as dark as possible.
Bed linen should be suited to the season and your sleep style. Belgian linen makes a great all-rounder due to its ability to cool and warm, as well as wick moisture. Cool and crisp, cotton is a fine choice for the warmer months. While silk makes for a luxurious quilt, enveloping you in a soft, gentle drape.
How you spend your waking hours is just as important for getting to sleep, says Dr Walker. Expose yourself to daylight first thing upon waking. This helps to build melatonin levels throughout the day, allowing you to more easily fall asleep at night.
Dinner should be consumed at least three hours before bed. Exercise too, if this is an evening activity. Abstain from caffeine after lunch. Alcohol too. Although it acts as a sedative, alcohol impairs REM sleep, an essential stage of sleep that firms up memory, processes emotions and resets key functions in the body.
In short, creating a sanctuary for sleep isn’t a luxurious indulgence. It’s as important for our health as, say, good quality running shoes, a fridge full of fresh fruit and vegetables, or a regular massage.