PSA: Light levels can matter a lot for mental health
It’s now November, and it’s getting much colder and darker in UK, and other northern countries. And when it gets colder and darker, this is pretty bad for my mental health - I get sadder, lethargic, more anxious, less productive, etc. I think this is a mild form of Seasonal Affective Disorder (SAD), or winter blues, a medical condition where people show symptoms of depression during winter, but not all year round. I think this is especially important to think about in 2020, when we’re all going outside even less than normal!
About a year ago, I realised that I should actually do something about this, and bought some really bright lights, which is pretty standard therapy for this. And this had a noticeable and positive effect on my mental health! Anecdotally, this is super common among my friends, but many people were macro-procrastinating about doing anything about this. And this is crazy! Getting really bright lights is a super cheap and low effort intervention, with some chance of meaningfully improving your mental health for a few months out of every year. I think it’s blindingly obvious that the expected value of doing something about this is super high, so I thought I’d write a quick post trying to motivate solving this problem, and giving actionable solutions.
Note: I am not remotely qualified to give medical advice. I expect this post to be uninteresting if light levels don’t affect your mood at all, or if you’ve already tried light therapy.
Why is this plausibly a problem?
SAD, which is when your condition is bad enough to count as clinical depression, is super common. Like, 9% of people in Alaska have it
Further, I think it’s much, much more common to feel a bit down, but not enough for it to count as depression. About 25% of people in Alaska have “subsyndromal” SAD (whatever that means). And feeling a bit down for a third of the year really obviously sucks and is worth doing something about
This means, outside view says that if you live in a Northern country, there’s at least a 1/3 chance that light levels noticeably affect your mood
Personally, I don’t think my symptoms are bad enough to count as depression, but it’s still a massive life improvement to reduce them! Symptoms that convinced me I should do something about this:
My mood improved when the Sun came out from behind a cloud, while I was outside
I felt more drawn to going outside on sunny days
I enjoy basking in the sun, and find this energising
I generally feel more tired during winter
I am more productive when working in spaces with good lighting. I get tired and strained quickly when working in a dim room
If you relate to any of these, I think it’s worth exploring this!
What can you do about this?
The obvious thing to try is light therapy - getting really bright LED lamps, and making your room as bright as you can get it!
I think the evidence base is a bit shaky here (this seems criminally under-studied relative to how common it is), but it makes obvious intuitive sense to me that this should work, and anecdotally this is effective.
Another commonly suggested thing is supplementing Vitamin D, since . I have no idea whether this actually works, but Vitamin D seems pretty safe, and plausibly protective against COVID, so this seems like pretty high expected value.
Why do many people do nothing about this?
It’s also pretty hard to tell for sure whether you have it! It’s pretty hard to diagnose, beyond high-level things like “do I feel sadder in winter”, which is hard to be objective about
It’s easy to just think this is normal, and not really notice it
It’s far from guaranteed that light therapy will do anything about this. It’s easy to be risk averse, and not want to bother, in case the money and effort is wasted
I think SAD is a classic case of macro-procrastination. It’s a minor drain on your happiness and productivity, that feels like a low-level background thing. There are no deadlines or urgency for doing anything about this, so it’s easy to always put it off
Doing anything is a high, one-off cost of effort. While doing nothing has many small, background costs, that feel like a default. It’s easy to do nothing in a situation like this
I think this logic is all clearly in error. The downside risk of buying a bright lamp is some money and some time, and you can stop if it’s not working. While if it does work you can keep doing it for the rest of your life. And the upside of a noticeable increase in mood for 1/3 of the rest of your life is insane - without even accounting for potential productivity benefits.
The evidence base is sufficiently shaky that I can’t say it’s guaranteed to work, but I think the chance is high enough that the value of information is super, super high!
I think it is thus very, very obvious that the expected value is high - seek upside risk!
Low-effort action points - I recommend doing your own research and digging into this more, but if you buy my case yet are unlikely to invest further effort, here’s what I’ve had success with:
Get a SAD lamp
I personally recommend Lumie - they seem to make good quality stuff, and have a 45 day free return period - reducing the downside risk to basically nothing. I expect you can get cheaper elsewhere.
I really like their Brazil lamp
Replace your lightbulbs with much brighter ones
This bulb is the brightest I’ve found that fits into normal lightbulb sockets, and pretty cheap. It’s about 8 times brighter, and I find my room a noticeably more pleasant work environment now.
Buy Vitamin D (take 1 pill a day, it’s recommended to take a pill before a meal, since it’s fat-soluble)
Further reading
I sometimes see people who try light therapy lamps, which are nowhere near as bright as true sunlight, and find them ineffective. So they get much brighter lights and have much more success with this. I personally feel happy with standard light therapy, but this is also worth trying if that fails
A good intro post: Your room can be as bright as the outdoors
If you’ve got this far into the post, and buy my case, but haven’t done anything about this, I’d once more highly recommend doing something about it. And doing something right now. Again - the downside is super low, and while it isn’t guaranteed to work, the potential upside is massive. I expect that spending some time fixing this is the highest expected value per unit time thing you could be doing today. And I think it’s a massive tragedy to procrastinate on low hanging fruit like this. What’s a first step you could take, in under 5 minutes, right now?
