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When we set clocks forward this past weekend and lost an hour of sleep in the switch to daylight saving time (DST), our routines were disrupted literally overnight.
While most people grudgingly accept this trade-off of sleep for more sun, others will find it damaging to their health. Research shows the reduced rest associated with the transition to DST can cause serious, lasting impacts on those with certain pre-existing medical conditions.
Working to uncover the many ties between sleep patterns and overall health is Dr. Azadeh Yadollahi. As lead scientist at SleepdB, Canada's first soundproof sleep lab located within the KITE Research Institute at UHN, Dr. Yadollahi studies the physiological changes that occur during sleep.
The innovations and technologies SleepdB develop enhance treatment for those with chronic disorders like sleep apnea and nocturnal asthma, and aim to reduce their risk of hospitalization.
A sudden change in body rhythm
Many biological processes are regulated by the body's sleep-wake cycle, called the circadian rhythm. This cycle, in turn, is driven by natural cues in the environment like the length of sunlight in the day.
According to Dr. Yadollahi, when clocks are changed for DST and a shortened sleep time is imposed on the body, it causes a sudden disruption to the flow of its internal rhythm.
"Vital biological systems and processes are finely tuned to work in a certain order, and daylight saving immediately interrupts this," she says. "When we lose one hour of sleep, we push the body to do all the things that it's used to doing over the night in a shorter span of time."
Many people experience fatigue as a side effect from the time change as their bodies work to compensate for the lost hour of sleep and adjust to a new cycle. This is sometimes manifested through increased accident rates or a reduced ability to concentrate.