Did you have trouble waking up this morning?
If you live in Europe, you might have felt more sleepy in the morning than usually over the past week after the onset of Daylight Saving Time (DST) has disturbed your inner circadian rhythm.
Switching to DST was implemented in many countries in Europe, Northern and Southern America as well as in parts of Australia and New Zealand. Originally, the idea to put the clock forward an hour in late March was conceived in order to decrease coal usage during wartime and later in the energy crisis during the 1970s. In addition to this economic reason, DST offers the advantage to spend more leisure in daylight and to make better use of sunlight.
Many studies have been conducted assessing the effect of this man-made time change on human health and behaviour. Although results differ from each other, the general consensus is that while DST is not specifically harmful, it does have detrimental effects on sleep quality.
Interestingly, scientists from Finland found that spring and autumn transitions have different effects on different people: While the spring transition is harder on people who prefer to get up and go to bed late (so-called owls), early risers – or larks – experience problems adjusting to the autumn transition.
Want to find out, which chronotype matches your personal preference? Take the test developed by Munich researchers:
A 2014 study showed that our body’s natural rhythms can be disrupted by the change. Cortisol is a stress hormone that is important in our metabolic activity, immunity, and sleep — it reaches its lowest levels in the middle of the night and peaks in the early morning. “Our data suggest this rhythm is resistant to the arbitrary changes in clock time with daylight-saving,” the researchers wrote. The hormone cortisol peaked almost a full hour later — 58 minutes to be exact — during daylight-saving time than it did after daylight-saving time ended, their analysis showed.
If you participate in the Kenkodo beta phase, you might already have answered the question whether you are a morning person or not a little while ago. We are thrilled to see how the metabolism of larks and owls might differ!
Ever since its implementation, there have been many critical discussions about whether or not DST is useful and/or necessary. In the past decades, more and more people appear to feel negative about the time switch: A recent poll by digital weather provider accuweather.com shows that over 80% of approx. 24,000 Americans do not agree with DST. German Forsa asked the same question to 1,000 Germans, of which 74% would prefer to stop DST.
Go to bed a little earlier as usual and try to get as much sun exposure as possible in the morning.
We hope you have recovered well from DST this year and are enjoying the sunny evenings!
Marleen from the Kenkodo Team
The Human Circadian Clock’s Seasonal Adjustment Is Disrupted by Daylight Saving Time – Kantermann et al., 2007
Daylight Saving Time Messes With Your Body Clock
History and Info – Daylight Saving Time
Transitions into and out of daylight saving time compromise sleep and the rest-activity cycles – Lahti et al., 2008
The effects of season, daylight saving and time of sunrise on serum cortisol in a large population – Hadlow et al., 2013
What daylight saving time does to your body