Pragmatic 21A: Daylight Saving Follow-up 1

20 July, 2014


Follow up (Part A) to Daylight Saving where we quickly touch on Seasonal Affective Disorder and whether Daylight Saving actually contributes to it. Thanks for the feedback Andrew McAuliffe.

Transcript available
This is Pragmatic Follow-Up Part A for Episode 21 Daylight Saving. I'm John Chidjie. Follow-up for the month of July is proudly sponsored by LIFX. Spelled LIFX, they're a smart, energy efficient, Wi-Fi enabled LED light bulb that you can control with your smartphone. You can change the brightness, color and tone from the app and it comes with a range of cool effects and it's really great fun to use. Visit LIFX, again spelled LIFX, dot co slash and use the coupon code 'Pragmatic' for 15% off the total price of your order. If you're a developer, there's SDKs for iOS, Android and Ruby and there's a competition currently open till the 25th of July 2014. So if you submit an app for controlling LIFX bulbs by that deadline, you're in the running to win enough LIFX bulbs to fill every light socket in your house as well as get free advertising for your app through LIFX. Check out the blog, it's for more information and be quick. So I had some feedback from, via the feedback form, from Andrew McAuliffe, I think it's pronounced, I hope I'm getting that right, please correct me if I'm not, regarding the issues of seasonal affective disorder. Now I didn't go into much depth into that in the episode, we're just talking about the mechanics of daylight saving rather than its effect on people, but it's a very good point. I actually, I did consider talking about it, but I didn't end up putting it in the episode. So now that I've had some feedback about it, I think it's relevant to talk about it just briefly at least. And seasonal affective disorder, there's a link in the show notes to tell a bit more about it. The idea is that people's moods will change based on the seasons. So during summertime, everything's all, there's a lot of sunlight, it's all bright and green. Well presumably, unless there's a drought on, or unless you live in the middle of the desert in any case, whereas in winter it is you know it's cold, there's less sunlight because the days are shorter, everything is brown or looks like it's dead or dying, at least that's the way I describe Calgary in the middle of winter anyway. Mind you there's a fresh beautiful sprinkle of snow on the ground, it's a beautiful fairy tale white and that's of course before it turns into slush and then it kind of breaks that little illusion but But anyway, bottom line is that SAD, Seasonal Affective Disorder, affects a not insignificant percentage of the population. It's less common in countries like Australia, however it generally seems to be in temperate and sub-temperate or sub-arctic climates. But the funny thing is that if you look at it in relation to daylight saving, there doesn't seem to be much of a direct connection. So having a look into this, what would cause seasonal affective disorder? The most predominant theory is that it's about the body's internal body clock, sometimes referred to as the circadian rhythms. And there have been a bunch of studies that have shown that there seems to be a bit of a weak link between the amount of light that your eyes are exposed to during the day and a disruption of the body's natural circadian rhythms. So you would think that a person's latitude where they live would heavily influence this. Now what they've done, a group of people have done a bunch of studies, these are linked in the show notes if you want to have a look into it. There's a study of people that lived in Fairbanks, that's in Alaska and it's very close to the Arctic Circle. And they basically in summertime they get, and in the worst part of wintertime, they get only four hours of sunlight. Of that, that's not even full strength sunlight either, that'll be including your twilights. So, with only four hours of sunlight each day, and they then compared that with a town in New Hampshire, and this particular one I looked that didn't specify the town, but let's just say in New Hampshire. And New Hampshire has, in the worst part of the winter, nine hours of sunlight, which is still not a lot really, but more than double. Now you would think that there would be more impact on the people living in Fairbanks, more people would have SAD than they would in New Hampshire, but that is not the case. So the study concluded that approximately 9% of people in Fairbanks were diagnosed with a form, and ranging from mild to severe, but a form of seasonal affective disorder. And it was exactly the same percentage, or if not, I think it was within about 6.7% of that was found in New Hampshire to have SAD. So statistically, I think it was more actually. I think it was on 9.6 or 9.7%. I didn't write down the number, but the point is that that's counterintuitive. And this is the problem, is that people say daylight saving must have an impact on people's circadian rhythms. But if it's true, surely that would happen 'cause daylight saving will come in in the summertime and you have to wake up early and when it's darker. But because it's brought in at a time at which it'll be darker for the first few weeks of daylight saving, if you normally got up at six in the morning, but days are getting longer and longer. So the point at which you're in the middle of daylight saving, you'll be getting up, it'll still be sunlight in most places. So it would only ever be a temporary situation. It would it be confusing to the body? Probably, but would it throw your circadian rhythms out, your body clock out? I'm not convinced that it would, not significantly. If it was noticeable and detectable, would only be brief. So there have been plenty of studies into this. It's not conclusive but it seems to suggest that there is either a very weak link or there is in fact perhaps no link. So in any case I want to thank Andrew for bringing that one up and it was something that I did consider addressing and now I have addressed that. So thanks for the feedback Andrew, really appreciate it.
Duration 6 minutes and 28 seconds Direct Download
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John Chidgey

John Chidgey

John is an Electrical, Instrumentation and Control Systems Engineer, software developer, podcaster, vocal actor and runs TechDistortion and the Engineered Network. John is a Chartered Professional Engineer in both Electrical Engineering and Information, Telecommunications and Electronics Engineering (ITEE) and a semi-regular conference speaker.

John has produced and appeared on many podcasts including Pragmatic and Causality and is available for hire for Vocal Acting or advertising. He has experience and interest in HMI Design, Alarm Management, Cyber-security and Root Cause Analysis.

Described as the David Attenborough of disasters, and a Dreamy Narrator with Great Pipes by the Podfather Adam Curry.

You can find him on the Fediverse and on Twitter.