This Sunday, March 12th, we “spring ahead” and set our clocks an hour ahead to gain an extra 60 minutes of sunlight……and lose an hour of sleep. At least, that’s how I see it.
Why do we do this every year?
The loss of time in the morning allows us more daylight hours in the evenings throughout the summer months. This may be helpful for those long summer evenings, but how does daylight saving time (DST) affect our bodies when we’re still wrapping up winter here in Canada?
One can’t help but wonder what happens to our internal clocks and the health of our eyes when we force them to adjust.
In most parts of Canada, clocks are pushed ahead one hour on March 12th, ahead of the spring equinox. Regions that don't use DST in Canada include most of Saskatchewan and some communities in B.C., Northwestern Ontario, Quebec, and Nunavut.
Daylight Savings Time was first proposed in New Zealand in 1895 to preserve daylight. Supporters of DST generally argue that it saves energy, promotes outdoor leisure activity in summer evenings, and is, therefore, suitable for physical and psychological health, crime rates, and business.
The science behind our body clocks
How the time change impacts you depend on your health, sleep habits, and lifestyle. The one-hour adjustment of our sleep patterns and schedules disrupts circadian rhythms. It interferes with cortisol levels, hormones that fluctuate throughout the day to help manage stress on the body and increase blood sugar when levels are low.
Moving our clocks in either direction alters our body’s natural time cue – light signalled to our brains through our eyes – for setting and resetting our 24-hour cycle. When we adjust our schedules, our internal clock becomes out of sync. Light suppresses the secretion of the sleep-inducing substance melatonin. So, as much as possible, it is essential to expose yourself to natural light during the daytime hours and avoid exposure to bright light in the evenings.
Adverse effects on our bodies
One study determined that people tend to have more heart attacks on the Monday following spring’s DST shift. Researchers found that heart attacks increased 24% on the Monday after DST compared with the daily average for the weeks surrounding the start of DST. Another study found that after DST, fatal traffic accidents increased significantly. After the clocks were moved forward in the spring of 2014, there was a 20% increase in crashes on Manitoba roads on Mondays compared to all other Mondays that year, according to Manitoba Public Insurance.
In general, sleep deprivation and fatigue make lapses of attention more likely to occur and play a role in behaviour that can lead to crashes.
Tips to help us cope
Specialists advise that people may benefit from paying extra attention to their health and sleep hygiene after DST begins. Here are some tips:
You can think of Daylight Savings Time much like jet lag, and the older you are, the harder it is to adjust. Give yourself about two days to reprogram yourself to the new time…and enjoy those lovely long summer nights.