Former Scienceblogger Boris Zivkovic, now at Scientific American, has an excellent post arguing that we should eliminate daylight savings time. Given that DST was invented to save energy, it may seem strange that I agree with him, but I do – mostly because there’s no evidence that it does, and the physiological effects don’t merit the change:
Whether or not DST saves energy is the least of the reasons why it’s a bad idea. Much more important are the health effects of sudden, hour-long shifts on our bodies and minds. Chronobiologists who study circadian rhythms know that for several days after the spring-forward clock resetting – and especially that first Monday – traffic accidents increase, workplace injuries go up and, perhaps most telling, incidences ofheart attacks rise sharply. Cases of depression also go up. As the faint light of dawn starts preparing our bodies for waking up (mainly through the rise of cortisol secretion), our various organs, including the heart, also start preparing for increased function. If the alarm clock suddenly rings an hour earlier than usual, a weak heart can suffer an infarct.
The reason for negative health effects of DST is that, in essence, the entire world isjet-lagged for a few days. Unlike some animals, like honeybees and reindeer, humans have a very robust circadian clock system that resists abrupt shifts.
Every cell in our bodies contains a biological clock which coordinates the events in those cells—for example, when gene transcription turns on and off, or when specific proteins are made. When we are exposed to a light-dark cycle that is different from what we experienced the previous days, some types of cells synchronize to the new environmental cycle faster than the others. Cells in our eyes, for example, may adjust in about a day, while cells in our brains take a couple of days. Cells in the digestive system and liver may take weeks. So, for weeks after the DST clock change, our bodies are like a clock shop in which each timepiece cuckoos at a different time of day—a cacophony of confusing signals.
Because Eli is autistic, time changes are something he just doesn’t grasp or register. It often takes us weeks or months to get him adjusted to an hour-long time difference (one of quite a few reasons why international travel with an autistic son doesn’t sound like a blast to me). I see just how hard the time shift is on his body and brain, and I know that mine is just slightly better equipped to compensate.
Moreover, as we all know, daylight savings doesn’t make any more daylight – it simply shifts us more towards a night-focused society, rather than a morning-focused one. The main reason I don’t like daylight savings is that I think it functionally encourages out tendency to stay up late and separate our sleep cycles from natural light. What the coming of spring should do is motivate us to get up earlier, not stay up later.
So yeah, let’s dump DST.