It’s daylight savings time this weekend, which means you’ll get a longer day – but at the expense of adjusting your sleep for the next few days.

Sleep is foundational. It’s key to healthy, happy days – but far too few Canadians are getting enough rest. And with daylight time this weekend, it’s likely even the most well-refined sleep pattern will be thrown off, at least a little bit.

(The seasonal adjustment means you will lose one hour of sleep as the clocks spring forward. It kicks off on Sunday, March 12, 2023 at 2 a.m.)

Here’s what to know about the importance of sleep for optimal health and how to get enough quality slumber.

Seven to nine hours of sleep each night is the recommendation for adults,

while children and teens need more rest.

How much sleep do I need?

It’s recommended that adults get seven to nine hours of sleep each night. Children, ages 5 to 13, need nine to 11 hours of uninterrupted sleep and teenagers, ages 14 to 17, should get eight to 10.

But as many as 13 million Canadians are not getting the recommended hours of shut-eye each night. Half the population struggles with some sort of sleep-related problem, experts from the Royal Ottawa Institute of Mental Health Research estimate.

“Sleep is one of the three pillars of good health, along with nutrition and physical activity,” says Charles Morin, professor of psychology and Canada Research Chair in Behavioural Sleep Medicine at Laval University’s Brain Research Centre. “If we don’t sleep well or have trouble sleeping, this impacts our mental and physical health. In return, if we are ill physically or we are stressed, this has an impact on our sleep. It goes both directions.”

A 2018 study published in SLEEP suggests that getting too much sleep is also detrimental to your health. The phenomenon, called “sleep inertia,” can be experienced as the grogginess one feels after a long, deep slumber.

Everyone has their own sleep sweet spot. So a good indicator of how well you’re sleeping may be whether you wake up feeling refreshed, rather than how many hours you spend in bed.

A lack of sleep impairs our immune system and increases a number of health risks.

Insufficient rest can also impair cognitive performance, mood and immune function.

What happens without enough rest?

Countless studies show lack of sleep does a number on our bodies and our minds.

It impairs our immune system and increases the risk of developing heart disease, obesity, high blood pressure, strokes, Type 2 diabetes, cancer and, for people over 50, may even heighten the risk of dementia. It can also impair cognitive performance, mood and immune function.

Insufficient sleep can lead to depression and anxiety, reduces memory and attention span, muddies clear thinking, depletes energy and makes us grumpy.

Being short on sleep can affect your diet, too. Studies show that people who are sleep deprived eat larger portions of food, snack more at night and are more likely to reach for high-carbohydrate and/or high-fat snacks.

Getting enough sleep is an investment that reduces stress and improves productivity. Good sleepers are less likely to smoke, more likely to exercise, and drink less alcohol.

What is the impact of diet on sleep?

Tweaking your diet – when and what you eat – can set you up for a better sleep. Research suggests that eating a healthy diet, plentiful in fibre-containing fruits, vegetables, whole grains and beans and low in refined carbohydrates and saturated fat, promotes a good night’s sleep.

A 2018 study suggested that those whose food intake closely matched the Mediterranean diet slept longer and were less likely to have insomnia than people who didn’t follow a Mediterranean diet.

Hallmark foods in the Mediterranean diet include fruits and vegetables, whole grains, pulses (e.g., beans and lentils), nuts and seeds. The main source of fat in the Mediterranean diet olive oil. Fish, poultry, eggs and dairy products (yogurt and cheese) are eaten several times a week, while small portions of red meat are limited to twice a week, at most.

Many of these foods contain anti-inflammatory nutrients, fibre and phytochemicals; inflammation in the brain is thought to contribute to poor sleep. Plant foods and seeds also contain, at various levels, melatonin and serotonin, sleep-inducing brain chemicals.