Albertans will lose an hour of sleep this weekend as daylight saving time (DST) begins Sunday with the clock moving forward one hour at 2 a.m. on March 8.
Many people are left with little time to adjust before returning to work and school on Monday, which clashes with the human circadian rhythm.
Experts say when clocks move forward, people lose sleep, and the body’s internal system doesn’t immediately adjust, creating a form of social jet lag that affects attention, memory, mental health, increases injuries, and overall cognitive performance.
Dr. Peyman Hajiazimi, a Calgary-based sleep medicine specialist and founder of the Sleep and Wake clinic, says the body cannot quickly adapt to the one-hour time change.
“A body cannot adjust with rapid change,” he said.
What the research says about daylight saving time
A 2024 commentary in the Canadian Journal of Public Health reviewed existing research on daylight saving time in Canada and found the spring clock change causes the greatest disruption to sleep patterns.
The authors argue that the one-hour shift misaligns light exposure with the body’s internal clock, leading to short-term sleep loss and reduced daytime functioning.
The researchers found, “the potential one-hour loss of sleep can contribute to the immediate negative impact of DST on daytime functioning, physical and mental health issues, as well as reduced overall performance.”
The DST shift occurs overnight from Saturday to Sunday, giving Canadians only one night to adjust before returning to school and work on Monday.
That very limited adjustment period can intensify fatigue at the beginning of the academic week, when students are required to be attentive, absorb new information and contribute to class discussions.
Given its major role in memory consolidation, any reduction in sleep can affect academic performance and achievement.
A brief form of jet lag
Hajiazimi compares the shift to a brief form of jet lag.
“For example, you flying to Manitoba and then when you fly to Manitoba you need to get out of bed one hour earlier and then your body experiencing some sleep deprivation.“
Hajiazimi said that people with insomnia, sleep apnea or other sleep disorders may feel the effects more strongly, adding ”one more hour of sleep loss could lead to loss of cognitive function and other issues.”
For students balancing coursework and exams, the impact may be immediate.
“Students, if they have exams, then within the next week of this time change, then it could impact their cognitive function and cognitive abilities in terms of what they need to do.”
The seasonal clock change has also renewed debate about whether Canada should continue switching between standard time and DST.
British Columbia recently announced it will adopt permanent DST after March 8, a change ending the twice-yearly clock shift that sparked discussion across the country.