
Sleeping in rooms with even a little light can increase risk of depression - WildGreenLeave
http://abcnews.go.com/Health/sleeping-rooms-lighting-increase-risk-depression-study/story?id=53636492
======
tzs
Sort of OT, but this reminds me of a question I've not been able to find an
answer for on blue light and sleep. (OT because the article says nothing about
blue light).

One way light affects sleep is via the intrinsically photosensitive retinal
ganglion cells (ipRGCs). These are a third kind of photoreceptor in our
retinas, distinct from the more well known rods and cones. These are most
sensitive to blue light. They signal the suprachiasmatic nucleus (SCN) in the
brain with information about the amount of light they are receiving. The SCN
controls circadian rhythms, and uses the changes in light as the day ends as
reported by the ipRGCs to do things like to keep things that should be
synchronized to the day/night cycle in sync.

Blue light in the evening can mess this up because it makes it look like it is
still daylight, as far as far as the SCN can can tell from what it gets from
the ipRGCs.

What I have not found anywhere is whether this is based on absolute or
relative amount of blue light. Does the SCN look for blue light to fall below
a certain fixed threshold, or does it do something like note the peak level of
blue light during the day, and then look for the blue light to fall below a
certain fraction of that?

The reason this matters is that more and more of our devices that we want to
use in the evening supply blue light. We try to counter that by adding
features that change the color spectrum in the evening to something with less
blue. But that doesn't always work. Computers usually can do it, and often so
can tablets and phones. I don't think many TVs have such a setting, though.

If the SCN works with absolute levels, fixing the devices (or wearing blue
light filtering glasses) might be the only answer if you aren't able to stop
using your devices in the evening.

But if it is based on relative levels, keyed off the peak daytime level...then
instead of fixing all the devices it might be possible to address the problem
by greatly boosting blue levels in the middle of the day, so that your evening
device levels will be far enough down from the peak to not affect anything.

~~~
RoboTeddy
IIRC from reading papers, there seems to be a dose-response effect, both w.r.t
intensity and match to peak sensitive wavelength (~465nm). Even green light
has some effect.

Avoiding blue light at night _after you go to sleep_ is definitely an under-
appreciated problem, especially for folks that stay up late. If you have a
habit of going to bed at 2:30am, and the sun rises at 5:30am and comes in your
window, you're getting blue light during your circadian night (enough light
can make it in through your eyelids to be a problem) -- this may screw up your
sleep schedule.

~~~
stordoff
Anecdotally, I know the amount of light that comes in between the window sill
and the curtain can throw off my sleep schedule - I tend to feel most alert
around 1am, so I'm a late sleeper, and when the sun rises early (~4:30am in
summer around here) I tend to feel unrested or I'm woken after only an hour or
two's sleep (and can't get back to sleep even after getting rid of the light).
Putting the curtain up on the window sill to block the light completely gets
rid of that effect.

Oddly artificial light (even with bulbs on the blue-end of the spectrum) tends
not to do the same -- if I'm woken for other reasons and use artificial lights
and displays then try to get back to sleep, or leave lights on in the room,
it's usually not an issue. No idea if that's some sort of dose-response effect
or a reaction to the sun cycling rather than being constant (or even placebo
potentially).

------
davidw
One thing I miss from Italy are _real_ shutters:

[https://blog.therealitaly.com/2007/08/09/window-
technology/](https://blog.therealitaly.com/2007/08/09/window-technology/)

~~~
tincholio
I grew up sleeping in pitch black darkness, and having lived now for a while
in the Nordics, where summer nights are light and curtains are mediocre at
best, I can share that feeling.

I wonder if the higher rates of depression here may have something to do with
this (interestingly, I remember reading somewhere that suicides in the Nordics
peak in Springtime).

~~~
kwhitefoot
I've lived in Norway (40 km south of Oslo for the last 32 years, generally
with only light curtains. Not noticed any tendency to depression or difficulty
sleeping in myself or my family.

Mind you, most hotels here that expect foreign guests have blackout blinds or
at least very heavy curtains,

~~~
tincholio
My first Summer in Finland, I was renting an apartment with crappy curtains. I
was dead tired through May, until I broke down and duct-taped large trash bags
to the windows. The difference in sleep quality was nothing short of amazing.

I have blackout curtains nowadays, and I've also gotten used to the light
somewhat, but I still miss proper rolling curtains that completely shut the
light out.

------
lkrubner
Should we assume that the light itself is causing the depression? Or should we
assume that the light leads to poor sleep, and then the poor sleep is what
triggers the depression?

~~~
WalterSear
And how does poor sleep causing depression square with sleep deprivation
alleviating it?

~~~
cellularmitosis
I could imagine that being chronically deprived of quality sleep is different
than skipping an entire circadian cycle once per week.

Edit: I recently made the mistake (for a few months) of taking my medication
before bed, rather than in the morning. This included vitamin D. Guess what
happens when the body gets a dose of vitamin D at night? No quality sleep for
you! So I certainly sympathize with the quest for quality sleep.

------
Herodotus38
In prehistoric times, before shelter was common, would a half or full moon
cause the same effect?

I just wonder about how actually natural a pitch black sleep is.

~~~
schiffern
>I just wonder about how actually natural a pitch black sleep is.

"Pitch black" is another thing entirely, but the moon is much dimmer than the
light levels this study reports as causing depression (5 lux). And it's pretty
dim (equivalent to stray light from a streetlamp).

>The intensity of moonlight varies greatly depending on its phase, but even
the full Moon typically provides only about 0.05–0.1 lux illumination

[https://en.wikipedia.org/wiki/Moonlight](https://en.wikipedia.org/wiki/Moonlight)

~~~
Herodotus38
Thanks for putting it into perspective. 5 lux is quite a lot to me.

------
jimnotgym
Quick plug I started curating a list of things that may help depression
yesterday over on Github
[https://github.com/Jimnotgym/Hacking_Depression](https://github.com/Jimnotgym/Hacking_Depression)

I just added this

~~~
O_nlogn
Please consider including links to local crisis helplines e.g. [1] and [2].
Doubtless some people in the midst of a crisis will discover this resource,
and it is really important that they are aware there is immediate help
available. [3]

[1] [https://www.samaritans.org/](https://www.samaritans.org/)

[2]
[https://suicidepreventionlifeline.org/](https://suicidepreventionlifeline.org/)

[3] [https://www.nuj.org.uk/news/mental-health-and-suicide-
report...](https://www.nuj.org.uk/news/mental-health-and-suicide-reporting-
guidelines/)

~~~
dprsthrwy
On the other hand you may turn away depressed people who are not in a crisis
because they don't want to be associated with the idea of suicide when their
main problem is they have no will or energy to do anything ever. You might end
up hurting these people by constantly mentioning suicide whenever they finally
get the guts to learn about their depression. "Oh, you depressed? Here, read
about suicide! Let me scare you back into your hole!"

-a once depressed person whose recovery was delayed by the association described

~~~
jimnotgym
You both make good points. I opened an issue to discuss. Please have your say.

[https://github.com/Jimnotgym/Hacking_Depression/issues/1](https://github.com/Jimnotgym/Hacking_Depression/issues/1)

------
gargarplex
I added a real blackout curtain to my room and really noticed a difference in
the quality of my sleep and my general mood. It was designed to really black
out all light...
[https://www.amazon.com/gp/product/B003ZJ88DY/](https://www.amazon.com/gp/product/B003ZJ88DY/)

~~~
sitkack
Ikea also has a great assortment of easy to install blackout shades,
[http://www.ikea.com/us/en/catalog/products/70349252/](http://www.ikea.com/us/en/catalog/products/70349252/)

~~~
maxander
What we ought to have is a blackout shade that will automatically roll down at
night and back up in the morning, when we _want_ sunlight to start waking us
up.

~~~
jpalomaki
Look for motorized roller curtain. I have those in two bedrooms. They are
actually very convenient, even though I just have the remote control and not
any automation. DIY persons can also find instructions for getting the shades
from IKEA and motors from Ebay.

Mine are using motors/control from Somfy. Those have at least worked
flawlessly for several years.

For the roller curtains there are also models which have "things" on the sides
where the curtain slides in. This blocks the light that would otherwise shine
in from there. If this is not an option, should look for curtain which is dark
from the outside. This should also help a little bit.

------
icebraining
Link to the study: [https://sci-
hub.tw/https://academic.oup.com/aje/article/187/...](https://sci-
hub.tw/https://academic.oup.com/aje/article/187/3/427/4056592)

~~~
noname120
This is worth noting:

> Our study has several potential limitations. First, participants were not
> randomly selected, possibly leading to selection bias. However, the
> parameters of BMI and estimated glomerular filtration rate were similar to
> corresponding national data in Japan and the follow-up rate was sufficiently
> high.

> Second, bedroom light intensity was measured without eye-level light meters,
> and sleep/awake status was measured only over 2 days.

------
navjack27
So does my body itself need to be protected from seeing light or just my
face/eyes? I'll just get a sleep mask.

~~~
computator
Skimming the original study, it talks about subjects opening and closing their
eyes, so I would very much assume that it's entirely related to seeing light
(and not about absorbing light through the face or body).

If you get a sleep mask, be sure to look for one designed to not put pressure
on your eyes, which are not hard to find if you seek it out. The cheap ones
you get at pharmacies and dollar stores put direct pressure on the eyeballs
and it's a wonder that anyone can tolerate them and are perhaps even harmful.

~~~
muzani
Any brands you'd suggest?

~~~
cgravill
Hibermate are very good, I use them especially when travelling. Original style
are reasonably priced [https://www.hibermate.com/products/the-original-
hibermate](https://www.hibermate.com/products/the-original-hibermate)

------
lhnz
I currently sleep in a room with zero natural light.

I can't tell you whether this makes me more or less likely to be depressed (I
think it pales in comparison to other things in my life), however I do always
keep a low light on -- without this, it would be very difficult to find my
bearings when I wake up.

Also, it is extremely difficult to wake up when it's completely pitch-black.

~~~
chrisper
Get a wake up light.

------
DoreenMichele
Light does not happen by magic and tends to not occur alone. I would be very
leery of asserting cause and effect here.

~~~
Nomentatus
There's a very long bibliography stretching back more than a decade and
including at least one mouse model of depression. It's not just one study.

~~~
DoreenMichele
I am not readily finding this bibliography. If you would be so kind as to link
to it (and perhaps copy/paste if it is paywalled.)

~~~
joveian
There are a bunch of results for "light at night" on Google Scholar and
Pubmed, but I'm not sure of specific references. This particular study (a
manuscript is available on sci-hub[0]) does not have a discussion of this
topic (other stuff that could come with the light) at all and two reviews I
searched for "noise" and "sound" did not seem to have a discussion either. I'm
sure some of the many studies over the years have at least actively changed
the lighting and measured melatonin, but it is sloppy to not even discuss the
topic.

In the case of this study, a figure at the end of the manuscript shows that
most of the light exposure (averaged) happens in the hour after bed and hour
before getting up, so that seems like a big clue that it isn't just a case of
light at night (ideally they would divide light exposure into three segments
and look at each). Also, the study started with people not showing depressive
symptoms but it didn't consider if light exposure had changed and the study
seems on the small (863 people) and short (median 2 year follow up) side if
light (and whatever else) exposure had not changed. For that matter, it sounds
like they only measured light exposure and sleep for two days and assume that
is representative of the whole period.

It sounds like the depression scale[1] was given at the beginning and end of
the study and looking at number or duration of episodes could have a different
result. Also, it isn't clear that depressive symptoms here necessarily
correspond with depression or if they are signs of a sleep disorder.

All in all, this isn't a good study to look at individually.

[0] [https://twin.sci-
hub.tw/ef19202b216d8e1af61a7ced2510e060/oba...](https://twin.sci-
hub.tw/ef19202b216d8e1af61a7ced2510e060/obayashi2017.pdf)

[1] [https://consultgeri.org/try-this/general-
assessment/issue-4....](https://consultgeri.org/try-this/general-
assessment/issue-4.pdf)

~~~
DoreenMichele
Thank you.

I am not going to be able to dig into the bibliography mentioned. I have been
skimming titles and I am not swayed.

I used to be on a health list where abstracts were frequently posted. I
stopped bothering to read the abstracts after speaking with a man with a PhD
in chemistry who told me the abstracts frequently claim the opposite of the
study.

A relative of mine works at the CDC and has had cancer multiple times. They
used to bitch at me about the lack of good cancer studies. The detail I recall
them lamenting was that basically you got dozens of variations on whatever the
latest funding craze was because researchers could get money for that and
maybe one out of a hundred studies was actually proposing a new idea, if that
much.

I have read bad studies. I have participated in bad studies. I have been on
health lists where people were asking for tips on how to qualify for studies
as a means to get free treatment. It looked to me like a form of gaming the
system in a way that would skew research results. I don't think they were up
to anything nefarious. They just had serious health problems and we're
desperate for help. But if you are getting tips for how to get into the study
that you don't currently qualify for, I cannot help but think that will skew
the study results.

I am generally a skeptical person anyway. But I am very leery of this kind of
research.

------
bitL
Slightly off-topic: I've noticed if I work all night (e.g. yesterday writing a
paper proposal for a conference), and I manage to stay up all the way until
dawn, I literally get euphoria once Sun glances through windows. I can be
super tired, but it shots my mood up considerably.

------
mrfusion
It seems like a study like this could have actually modified the light levels
and measured the changes.

~~~
icebraining
Actually, they didn't touch the lights at all, they only measured the lights
that people already were exposed to. They write that "an interventional
method, such as a randomized controlled trial using a LAN exposure, is not
possible because of ethical concerns".

~~~
mrfusion
I can’t imagine minor adjustments to light levels could ever be considered
unethical. Is it unethical when a city installs a new street light?

~~~
dpark
It’s unethical to do X when X is expected to harm the study subjects.
Exceptions are sometimes made for interventions with terminally ill patients,
but in general studies that are expected to harm subjects are not approved by
ethics boards.

They could reasonably do an intervention study that only reduces bedroom light
to confirm if that corrects depression on subjects.

------
homero
I think a lot of studies like this are just wrong. When I was a kid, I
couldn't sleep without a light on because I'd get depressed. So later on in
life if I didn't remember that, I'd think that I just had a light on and now
I'm depressed. I think depressed people like a little light.

Much like they say red meat causes cancer, I don't think it's the red meat. I
think it's how it's cooked. Red meat is usually barbecued and that char is
what could be causing the cancer.

~~~
boomboomsubban
>So later on in life if I didn't remember that, I'd think that I just had a
light on and now I'm depressed.

What? Anyway, this study has strict definitions of what "depression" is, and I
doubt whatever you felt as a child would qualify.

>Much like they say red meat causes cancer, I don't think it's the red meat. I
think it's how it's cooked. Red meat is usually barbecued and that char is
what could be causing the cancer.

They say eating red meat may cause cancer. Even if your guess is true, they
would still be right as red meat is often barbecued. And as a larger point,
thinking something like this is true doesn't matter until you get evidence for
it.

~~~
homero
If I didn't remember why I wanted light on.

They would be right about red meat but the point would be lost if people begin
switching to bbqing chicken and still get cancer.

~~~
boomboomsubban
I still think you're confusing whatever feelings you felt with clinical
depression.

>They would be right about red meat but the point would be lost if people
begin switching to bbqing chicken and still get cancer.

The study was showing a link they found, they weren't giving a diet
recommendation. But, it would only be lost if your guess was correct and
everybody that made the switch barbecued as much chicken as they did beef.
Otherwise, fewer people would develop cancer than if the scientific study had
not been published.

------
analogic
They still use go.com?

Lol, everytime I see that domain all I can think of is it being the place
where Infoseek went to die.

------
hawski
Meanwhile:

22\. ▲ The antidepressant effect of sleep deprivation (mosaicscience.com)

389 points by onuralp 1 day ago | flag | hide | 135 comments

~~~
Broken_Hippo
Sleep deprivation is different from sleeping poorly.

~~~
Izkata
Both articles are talking about depression, neither is about sleeping poorly.

------
GoToRO
What I don't like are the "solutions" they propose: noise? use earplugs,
light? use curtains. Well I will not be able to sleep if I have something in
my ears and if you pull the curtains then you can no longer wake up naturally
with the Sun. How about changing your lifestyle so that you can have silence
and dark during the night and light in the morning without any "devices". You
might have to quit your job :)

~~~
icebraining
So other people should change their jobs because you can't sleep with
earplugs? Seems like a curious way to see the world.

Regarding light, if you want morning sunlight, motorized curtains with a timer
are cheaper than moving.

~~~
cup-of-tea
He didn't say that other people should change their jobs for him. He said they
should change their jobs instead of having to sleep with earplugs or curtains.
But I think he fails to realise that many people live in _very_ different
environments to him.

------
exodust
> _those exposed to more than five “lux” of light each night had higher rates
> of depression_

Light can be measured, depression cannot. It barely even has a definition, let
alone quantifiable rate. I'd sooner believe that auto-playing videos had a
stronger link to depression than lux.

Random theory... Maybe depressed people are highly sensitive to the world's
problems/suffering both in immediate and wider environment, their antennae
picks up this instability that manifests as internal trauma, anxiety etc.
Someone should do an experiment to see if isolation for a few weeks influences
depression rate; avoidance of all news, no phone, no internet, no people. Get
ready for "Study finds extreme boredom effective anti-depressant".

