Wake Up to the Real Effects of Daylight Saving
It’s November 5th. Daylight saving time (DST) ends and Standard Time (ST) begins. Clocks go back. We all get an extra hour of sleep. Life goes on. Like the rest of the world, I was always torn on the whole concept.
On one hand, I hated that it got dark at 4 pm and I felt like I was ready to crawl into bed at 7. On the other hand, maybe it’s a good thing that we got more sunlight in the morning. I was never 100% sold on this seemingly arbitrary concept, but after specializing in the field of sleep and learning more about the astounding effects to our sleep and other body systems, I’m on team Ditch the Switch!
A brief history of Daylight Saving:
The idea of daylight saving was first proposed by an entomologist in 1895 in New Zealand, in hopes of gaining more after-work daylight hours in the summer. But it wasn't put into practice until World War I, when Germany used it as a way to save energy by using less electricity on lighting. The Canadian government followed suit to increase production during wartime, but then ceased the practice after WWI was over, only to resume it during WWII.
Fast forward to today and critics argue that we’re consuming energy in other ways, such as watching TV, using air conditioning and heating systems and driving, and we’ll consume energy regardless of what the time is, so the original principle is outdated.
Springing forward and falling backward:
Every year I hear the same complaints from friends, family, clients and especially parents with young children that the turning forwards or back of the clocks messes with their sleep schedules and alertness during the day. It’s not just for one night – many describe it as a multi-day and sometimes weeklong disruption to their sleep. And they’re not wrong.
In fact, there are mind blowing stats about what happens to us as a society when we collectively shift our sleep by an hour forward or backwards. Studies have linked it to higher rates of stroke and a bump in heart attacks, and interruptions to circadian rhythm can also impair focus and judgement, with a measured increase in fatal car accidents (up 6%) during DST.
Our mood gets affected as well. One study showed that hospitals reported an 11% increase in depressive symptoms (particularly seasonal affective disorder) just after the Fall time change. Suicide rates in males also increase in the days following the switch from DST to ST.
While fewer negative health effects are associated with “falling back” in autumn vs “springing forward” in spring, they still exist.
Why does Daylight Saving do this?
Remember what I told you a few blogs back about our circadian rhythm and how it helps balance and regulate our sleep/wake cycle, which is also connected to our physical, mental and behavioural processes and systems in our bodies? Your circadian rhythm is connected to a master clock which is located in your brain and this master clock is directly influenced by environmental cues, especially light. Light and darkness serve as critical external cues that influence the signals to coordinate the various internal processes in the body. While other cues, like exercise, social activity and temperature can affect the master clock, light is the most powerful influence on circadian rhythms.
So, when we alternate the amount of light we’re exposed to, even by just an hour, it can have a profound effect on our sleep (such as sleep deprivation or insomnia), as well as other systems in our bodies due to the misalignment of our circadian rhythm.
This is best illustrated when you’re flying long distances and experience jet lag. When you travel across multiple time zones without giving your circadian rhythm time to catch up, your body is all out of sync. For a few days after arriving at your new destination, you’re falling asleep or waking up at inappropriate times, finding yourself hungry at atypical times, you may experience cognitive fog or digestive problems. This is the result of what happens when your body’s natural schedule is out of sync with its new environment.
It’s generally agreed that it takes about 1 day per time zone to re-acclimate and rebalance your body’s internal clock, and there are definitely things you can do to help make the transition easier by adjusting your bed and wake time schedule, eating and caffeine schedule and light schedule before your flight. My hack for this is an amazing app called Timeshifter that does exactly this with incredible results. Last year I took a 3-night trip to the UK and a more extended holiday to Turkey and hit the ground running, with no jet lag.
Regularity and routines versus social jet lag:
Our bodies like regularity and a schedule because it helps balance all the integrated systems in our body, including our sleep system. If we’re going to bed and waking up at the same time, our bodies like that predictability, and in turn, we will start to feel tired around the same time each night and will feel alert and awake around the same time each morning (granted other things in your life are stable).
Lack of a bedtime routine and keeping an inconsistent schedule for both wake time and bedtime has a huge impact on sleep. One of the most common sources of sleep disruption is keeping an inconsistent schedule. How many of you keep different hours on the weekdays versus the weekends? Maybe staying up a bit later on Friday and Saturday night and sleeping in? And how many of you find it difficult to get to bed on Sunday night? As a society, we are suffering from what we call ‘social jetlag’, which means we’re keeping a somewhat regular wake and sleep schedule during the week but vary it completely on the weekend. And we wonder why it’s hard to get to bed on Sunday night and why we have the Monday blues the next day…
For some reason, social jet lag gets a pass and is almost swept under the rug in terms of its detrimental effects on our bodies and brains. Studies show that social jet lag is associated with an increased risk of obesity, metabolic syndrome, cardiovascular disease, and depression, yet DST or travel jet lag gets the bad rap. After arriving home from a trip abroad you might hear “you must be so jet lagged” but we collectively choose to ignore what we’re doing to our bodies each and every week.
Preparing for the switch to Standard Time:
To minimize disruption to our sleep wake/cycles, it's best to prep our bodies gently for the change. A small shift in our schedules will minimize the negative impact of the clocks turning back and will leave you less discombobulated than you normally would be.
Try these steps to help make that shift to wintertime a bit more manageable for you:
4 days before the clocks go back, gradually shift your bedtime 15 min later each night and wake up time 15 min later. When the clocks go back, your body will already have prepared itself for the time change in the days before!
Shift your meals to match the same as above.
Get bright light first thing in the morning and dim lights in the evening. Exposure to bright light in the AM will send a strong signal to your brain that it is morning and time to be alert. Exposure to natural, outside light is ideal, and soaking it in without sunglasses is best! Conversely, limiting bright light in the evening will send a signal to your brain that it is night time and will help induce the production of melatonin (a sleep hormone).
Stick with your usual bedtime routine. Ideally, you want to dedicate between 30-60 min to a relaxing, wind down schedule that limits bright light exposure and integrates activities that are calming for your mind and body.
Anchor your wake time. Don’t use that extra hour of sleep as an excuse to stay up late or sleep in later. Keeping a fixed wake time will help regulate your circadian rhythm and stabilize your sleep drive.
Exercise. Any movement during the day helps tire out your muscles at night and release feel good endorphins, which reduces stress levels. Two things that are helpful when you are trying to get to bed!
The call to end the bi-annual time shift is gaining momentum. Whatever your thoughts are on the DST/ST debate, for the moment we still need to adapt to it. I’m curious to follow the discussion around the topic and whether the increasing amount of research will lead to an abolishment of the practice. Currently Arizona has got rid of it, along with China, Russia, South Africa and a number of other countries and states. If, like me, you're still living somewhere that shifts the clock forward or back twice a year, remember that there are simple ways to minimize disruptions to your body’s internal clock.
