I was impressed by this part:<p>> In recent years, light therapy has experienced something of a backlash in Sweden, and Malmö’s clinic is one of only a handful that remain. In part, this was a response to a 2007 study by the Swedish Council on Technology Assessment in Health Care, which reviewed the available evidence and concluded that “although treatment in light therapy rooms is well established in Sweden, no satisfactory, controlled studies have been published on the subject."<p>My first thought was "Wow, a whole country that reacts to scientific articles and statements about the lack of controlled studies."<p>(Of course, the article goes on to say that light therapy shouldn't really be discredited yet, as controlled studies are hard.)
Long article, but here is the main part:<p>> Leading theory is the ‘phase-shift hypothesis’: the idea that shortened days cause the timing of our circadian rhythms to fall out of sync with the actual time of day, because of a delay in the release of melatonin. Levels of this hormone usually rise at night in response to darkness, helping us to feel sleepy, and are suppressed by the bright light of morning.<p>Edit: And alternative hypothesis from the article:<p>> When melatonin strikes a region of the brain called the hypothalamus, this alters the synthesis of another hormone—active thyroid hormone—that regulates all sorts of behaviours and bodily processes.
I don't know why some people love sunlight, but in my case, normally, it's make me angry, sleepy and tired.<p>Winter days, on the other side, make me start being productive again, start to run, have healthy food, stick with a nice routine and have a good mood, specially on drizzling days :)<p>And i know i'm not the only one.<p>Also, i enjoy night life a lot and, before starting working, always lived my life during the period from 16:00 to 8:00. I did that more than my half life. (Of course, my eating times were found weird for most people)<p>PS: I don't know if is unrelathed or not, but i'm diagnosed with hypothyroidism. And not, i'm not antisocial, depressive, bipolar or anything like that.
Details on the neuro-chemistry:<p>The mechanism for translating light into mood starts in the suprachiasmatic nucleus*, which sits right behind where your optic nerves cross.<p>Light-sensitive nerves trigger and transfer that information to the pineal gland, which in turn, starts breaking down serotonin to melatonin.<p>I dream about a brain implant that artificially stimulates the SCN. Control that stimulation and you control sleep, serotonin, melatonine, hunger, cell-growth, stress etc. etc. etc.<p>[0] <a href="https://en.wikipedia.org/wiki/Suprachiasmatic_nucleus" rel="nofollow">https://en.wikipedia.org/wiki/Suprachiasmatic_nucleus</a>
I live in Salt Lake City, and during the Winter it gets significantly darker.<p>I can definitely notice a difference in my mood and well-being when it's brighter outside. It becomes like hunger or thirst where you're craving some sunlight, and if you don't get it, you'll feel bad.<p>At least, that's my experience.
I took a trip to Longyearbyen a couple months ago when there is zero sunlight. That was the first time in my life I did not see the sun rise, and I stayed there for a week.<p>It was an interesting experience, and the nighttime landscapes were spectacular, but I would probably not want to live there for a long period of time.<p>In my normal work schedule I often get up at 5am, take a short hike or bike ride and watch the sun rise, then head to the office. It makes the day a lot happier and efficient when I start the day with a little time when I get to see the sun, be myself, and don't have to deal with people.
Many polls indicate Alaska as one of the "happiest" states in the US. I would argue that it is what you make of the light and/or activity level that makes a bigger difference. I live in Fairbanks, Alaska, and we have very minimal sun for half the year (3.5 hours at the solstice). Then you don't see darkness from ~April to ~August. Those who bundle up and get out regularly (ski/ice skate/play hockey/fat bike/walk/dog sled/watch northern lights) enjoy even the -40 degree dark winters.
Coming from Sweden but now living in Barcelona, at least I feel happier. Could probably be because of many reasons but I'm fairly sure the amount of sunlight matters a lot.<p>In sweden during non-summer (which is like 9 months during the year), you go to work in the darkness, witness the sun coming up for a few hours and when you leave work, the sun is nowhere to be seen again. I just remember feeling a lot more tired.<p>In Barcelona I wake up with the sun, can see the sun the entire day and still have time after work to catch some hours of 100% sunlight outside before it gets dark.
TLDR: Being in the sun makes you feel better.<p>That's about as obvious a conclusion as discovering that if you're thirsty you can drink water to feel better.
Yeah yeah, let's go on about the "virtues" of sunlight. I thought this was Hacker News?<p>Anecdotally, I've found it much harder to concentrate on intellectual tasks (eg programming) with bright daylight, even if it's entirely diffuse. Similarly, lack of a standard height white ceiling is extremely demotivational to doing non-computer tasks at night.