
Vitamin D supplementation to prevent acute respiratory tract infections (2017) - luu
https://www.bmj.com/content/356/bmj.i6583
======
bad_user
I suffer from allergic asthma and tend to catch colds quite frequently.

This year I started supplementing with 2000 UI of vitamin D daily and it's as
if my immune system started functioning normally, in the last 10 months I only
caught a really light cold that I could barely notice, whereas before this the
winter season alone would bring 2 severe cold or flu episodes that would knock
me down for several days.

I can't really say if it's the vitamin D, or other changes in my life, like
losing some weight or walking more, or the cold exposure I've been practicing
(primarily because I heard it burns calories :-)), it might be even placebo, I
haven't isolated these variables well, but my wife and close ones are amazed
by the transformation. E.g. 3 weeks ago everyone in my household got the flu,
except for me.

So now I got everyone in my household on vitamin D, especially b/c of this
coronavirus scare. During summer time we might not need it, but the sun
doesn't see us during winter. And vitamins are probably no defense against the
coronavirus, but a deficiency could amplify the damage (as vit D has a role in
our immune system) so it's best to ensure that we aren't deficient. Also we
tolerate large doses of vitamin D, so it can't hurt.

~~~
PaulRobinson
I have a really funky immune system. I have psoriasis for starters, and in
2017 I had to have neurosurgery to remove strep B from my spinal column and
learn how to walk again because my immune system hadn't been able to fight it
off.

I have reduced my alcohol intake, lost weight and have been taken medication
that isn't an immunosuppressant (acetretin), for the psoriasis, along with the
NHS giving me a free flu jab as I'm in an at-risk group despite being only in
my early 40s.

I was taking vitamin D back in 2017 after it was recommended to me by one of
the doctors, but slowly got out of the habit, and I'm now wondering if it can
help with some of this. I have a jar of 3000 UI knocking around, so I'll start
taking it today, and see how this goes - I have an outward looking signal on
how well my immune system is behaving based just on my skin condition, which
I've lived with for years so should be a good indicator of whether it improves
or not.

If you want to know more, just ping me via the channels mentioned in my
profile and I'll happily update in a month or two - let's see if I can provide
a sense of it!

~~~
hexl
I had MS-like symptoms about 2 years ago: weird sensations on my skin, sudden
pain spots, random ant-like crawling sensations, etc... they were getting
worse but MRI came fine, Spinal Fluid testing came fine, etc...

However, my vitamin D levels were low. I started taking D3 and noticed that
some symptoms got worse at first but gradually went away after a few weeks.
Now, every time symptoms come back, I take vitamin D and they are gone a few
days later.

------
neuronic
May I mention the following research on NCBI:

[https://www.ncbi.nlm.nih.gov/pubmed/28768407](https://www.ncbi.nlm.nih.gov/pubmed/28768407)

I will simply quote from the abstract:

> This could lead to a recommendation of 1000 IU for children <1 year on
> enriched formula and 1500 IU for breastfed children older than 6 months,
> 3000 IU for children >1 year of age, and around 8000 IU for young adults and
> thereafter. Actions are urgently needed to protect the global population
> from vitamin D deficiency.

Essentially, the recommended intake that pharmacists and labels tell you is
outdated and founded in a statistical error. Adults are recommended to take
>8,000IU every day and not ~1,000IU as still believed by many professionals
who last updated their brainbase decades ago.

~~~
elric
I'll counter that with a quick quote from wikipedia:

> Recommendations stemming for a single standard for optimal serum 25(OH)D
> concentrations ignores the differing genetically mediated determinates of
> serum 25(OH)D and may result in ethnic minorities in Western countries
> having the results of studies done with subjects not representative of
> ethnic diversity applied to them. Vitamin D levels vary for genetically
> mediated reasons as well as environmental ones.

Basically, rarely is anything simple enough for a "one size fits all"
approach.

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

~~~
aldoushuxley001
I wouldn't say you 'countered' OP with that quote, but you did add some very
pertinent and helpful info. From my perspective, though, your info is
syngergistic with OP's, not counter to it.

------
mherdeg
As a layperson it feels to me like research in the "megadose on vitamins to
prevent illness" area is kind of tainted by the legacy of Linus Pauling, who
was no doubt a genius in his fields and whose published literature advocated
the position that vitamin C megadose would reduce cancer deaths by 75% (
[https://www.theatlantic.com/health/archive/2013/07/the-
vitam...](https://www.theatlantic.com/health/archive/2013/07/the-vitamin-myth-
why-we-think-we-need-supplements/277947/) ).

I guess we know how to avoid the trouble -- make hypotheses and test them. The
trouble there is that the placebo effect is not a bad thing -- if you're doing
things which you think will improve your wellness and it works, who cares
whether there's a chemical mechanism? It works!

~~~
hannob
> The trouble there is that the placebo effect is not a bad thing -- if you're
> doing things which you think will improve your wellness and it works, who
> cares whether there's a chemical mechanism? It works!

That's an exceptionally oversimplified view on the placebo effect.

There's a very obvious issue: If you take something that helps you due to
placebo it may still also harm you due to its side effects. Some vitamins have
been shown to increase overall mortality.

But there's another issue, and that is that often what people observe isn't
the placebo effect, but something called "regression to the mean". Which is
basically the effect that you may take something and you get better, though
you would've gotten better anyway, because that's the natural progression of
the disease you have. This is very likely a bigger reason for all the "I took
it myself and got better, so I know it works!"-stories out there than the
placebo effect. And the "who cares why it works?" argument doesn't count for
regression to the mean.

~~~
raxxorrax
From the parent comment:

> who cares whether there's a chemical mechanism? It works!

There probably even is a chemical mechanism that improves your health. Mental
conditions like fear increase your heartbeat, respiration and muscle tonus,
being relaxed does the opposite. Stress is a factor we know is
contraproductive for the immune system and general health.

The effects have severe limitations of course and I don't think you can take
anything to "trigger" the placebo effect. You need the healthy self deception
part for it to work.

------
jpdus
I am a bit perplexed. Haven't almost all randomized/controlled trials shown
(e.g. [1]) that there is basically no measurable effect for healthy people?
All "positive" stories are relying on observational studies with the usual
confounders, right?

EDIT: Look at figure 2 in the Paper. Looks pretty random to me. Result is
almost exclusively driven by 4-5 small (<250 participants) and old studies.

[1] [https://www.vox.com/2018/10/4/17933880/vitamin-d-health-
sun-...](https://www.vox.com/2018/10/4/17933880/vitamin-d-health-sun-diet)

~~~
CodeWriter23
Vitamin D in the study you provide, D2 & D3 in the OP link. Chemistry and
source matters. D is synthetic, D2 is plant derived, D3 animal derived.

~~~
aldoushuxley001
D3 mostly comes from fungi as far as commercial sources for supplements are
concerned, I'm pretty sure.

~~~
posix_me_less
D3 is made by irradiating lanolin (from sheep wool) with UV light [1]. Natural
source of D3 is oily fish, beef liver. It's the Vitamin D2 that is made from
fungi - UV light helps to create it in mushrooms [2].

[1] [https://www.quora.com/What-is-the-industrial-process-
involve...](https://www.quora.com/What-is-the-industrial-process-involved-in-
making-Vitamin-D3?share=1)

[2] [https://ods.od.nih.gov/factsheets/VitaminD-
HealthProfessiona...](https://ods.od.nih.gov/factsheets/VitaminD-
HealthProfessional/#h3)

------
kasperni
This is a personal experience. But I've been struggling with constant throat
infections, tiredness and coughing every winter for years (I live in a Nordic
country). Had my 25-Hydroxy-Vitamin D(D3+D2) checked in both autumn and winter
2 years ago. In October it was ~ 110 nmol/L and in February it was ~ 30
nmol/L. (Deficiency is around 50 nmol/L).

Seeing the seasonal difference was a bit of an eye-opener. And I have been on
high dose Vitamin D supplements this winter. And all of my "winter" issues
have more or less disappeared.

~~~
dharma1
how high is high dose for you?

~~~
kasperni
4,000 IU 4-5 days a week. I did a loading phase with a bit more.

~~~
agumonkey
so the program is > 4000 at first then stabilize around 4000 ?

~~~
kasperni
Yes, I didn't start until late December so I did a little loading with a
bigger dose [1]. Next time I'm just going to start around October instead of
running into a deficiency.

[1] [http://gmmmg.nhs.uk/docs/nts/NTS-Recommendation-on-
Vitamin-D...](http://gmmmg.nhs.uk/docs/nts/NTS-Recommendation-on-Vitamin-D-
deficiency-and-insufficiency-adults.pdf)

------
KaiserPro
Table 4:

> _When all studies were analysed together, no statistically significant
> effect of vitamin D was seen on the proportion of participants with at least
> one upper respiratory tract infection, lower respiratory tract infection,
> hospital admission or emergency department attendance for acute respiratory
> tract infection, course of antimicrobials for acute respiratory tract
> infection, or absence from work or school due to acute respiratory tract
> infection. However, when this analysis was stratified by dosing frequency, a
> borderline statistically significant protective effect of daily or weekly
> vitamin D supplementation against upper respiratory tract infection was seen
> (adjusted odds ratio 0.88, 0.78 to 1.00; 4483 participants in 11 studies,
> P=0.05; table 5⇓)._

Which to me makes it sound like it makes almost no difference.

 _Edit_ : The above could be for pre-exsisting patients.

~~~
tomthe
You quoted the paragraph for the secondary outcomes, which doesn't diminish
the results quoted in the headline.

Said that, the effect of the main outcome is not that big (if I read that
correctly, it reduces your chances of getting a respiratory disease by ~4%)

------
drgoodvibe
I had a genetic test done (not 23andme or other retail genetic tests) and it
turns out I have genes that essentially cause me to have low absorption for
vitamins d, b6 and b12 and vitamin e. According to my bloodwork I also had
extremely low Vit d in the blood (way below average). I started megadosing and
honestly I feel like a different person, when I got a cold before it would
last for 7 days, and twice it led to bronchitis and then pneumonia this year
since megadosing I’ve had two colds and both lasted no more than 2 days. So
I’m not superman, I still get sick but the severity of the colds have been
significantly lower than before megadosing.

~~~
52-6F-62
My B12 deficiency was discovered because of a routine blood test. Low
hemoglobin, but since anemia runs in the family the rest was simple enough for
my GP to put together.

Eat more red meat (I rarely touched it in the past), and take a daily
supplement was the charge. The mental clarity and well-being improvements are
palpable.

------
leto_ii
I can say from my own experience that the lack of vitamin D can have a
significant impact on both mind and body.

I suspect that essentially all people living at relatively northern latitudes
have some sort of vitamin D deficiency. From what I know you need to have your
face and arms exposed to direct sunshine for at least 15 minutes/day to keep
healthy vitamin D levels in the body. Good luck with that in the
European/Canadian/Northern US winter.

~~~
thinkingemote
Its not possible to get any vitamin D from the sun in the winter in these high
latitudes even if you outside in the sun all day with short sleeves. The angle
of the sun is too low. We are just beginning march now, so the sun should soon
be beginning to be high enough to give some benefit.

~~~
kaztal
Sweden here. My partner is a doctor, she claims with assurance that you can't
make a carpet decision like this. People who come from norther latitudes are
used to the lack of sun, and their bodies don't need more vitamin D than is
provided. Depending on your heritage, ymvm.

~~~
abainbridge
That seems implausible. Obviously there was evolutionary pressure on northern
Europeans to tolerate lower levels of sunlight and no doubt adaption happened.
However, I expect even Swedes evolved in an environment that included more
time outdoors than a modern Swedish office worker gets. So, in the absence of
any actual evidence, I'd still expect a problem. On top of that, there is some
evidence. Basically all the papers found by this search show some evidence of
vitamin D deficiency in Swedish people:
[https://scholar.google.com/scholar?start=10&q=sweden+vitamin...](https://scholar.google.com/scholar?start=10&q=sweden+vitamin+d&hl=en&as_sdt=0,5)

~~~
SketchySeaBeast
The first two articles I get from that search looks at vitamin d and the older
population, and the third[1] suggests that even in sub-arctic elevations
"Adequate levels were found in 79.2%, more often in women (82.7%) than in men
(75.6%). Only 0.7% of the population were vitamin D3–deficient but 23.1% of
men and 17.1% of women had insufficient levels." That doesn't seem too
damning.

At the end of the day I don't know enough, so I'm not making the claim about
Vitamin D quantities, but isn't the evidence that there was at least some form
of adaptation evident based upon skin tone alone?

[https://www.tandfonline.com/doi/full/10.3402/ijch.v74.27963](https://www.tandfonline.com/doi/full/10.3402/ijch.v74.27963)

~~~
abainbridge
I already agreed there was adaption. I just can't see how there can have been
adaption for an _indoor_ life at northern latitudes. That's doubly hard,
compared to a traditional life in northern latitudes, right? Although, to
argue against myself, I guess if you go far enough north, people won't be
getting any sunlight in the winter even if they are outdoors all the time.
People there must have adapted to that. I guess by eating things with lots of
vitamin D.

------
darkerside
I've been wondering why it is that virus infections are supposed to
"disappear" in the summer. Obviously the viruses don't actually go anywhere,
so I would expect people to get sick year round. Maybe immunity boosting from
Vitamin D could be part of the answer.

~~~
dtjohnnyb
That is one hypothesis, though there are a lot
[https://en.wikipedia.org/wiki/Flu_season#Cause](https://en.wikipedia.org/wiki/Flu_season#Cause)

~~~
Gravityloss
Mind boggling that this kind of a thing isn't known. This says the total
economic effect of seasonal influenza in the US alone is 87 billion per year.
That's six NASA:s worth:

[https://www.sciencedirect.com/science/article/pii/S0264410X0...](https://www.sciencedirect.com/science/article/pii/S0264410X07003854)

~~~
Marsymars
> Mind boggling that this kind of a thing isn't known.

I was blown away recently when I discovered that the causes of myopia aren't
really known, but don't seem to be primarily genetic.

~~~
gameswithgo
some evidence that being indoors too much when young could contribute.

~~~
Marsymars
Yeah, possible related to sunlight causing dopamine release which inhibits
excess growth in the eye, but nothing close to the point of say, public health
authorities giving concrete parenting advice based on that.

------
kbrisso
Magnesium, vitamin D, zinc and mk-7 vitamin k-2 are my daily vitamins coupled
with a lot of exercise. I can't say when the last time I was sick.

~~~
Krasnol
I take not vitamin supplements at all, drink my Earl Gray with citron and
sugar and spend most days of the year in buildings in front of a computer
while travelling between them using public transportation. I don't even get
enough sleep.

I don't get sick while people around me do.

There is no one solution fits them all.

------
hannob
Please note that this is a bit older (2017).

As I personally have a cold quite often I was curious to look into this a bit.
Around the same time another metaanalysis was published with a similar
question [1], but quite different results (i.e. Vitamin D is unlikely to
help).

Here's [2] an (unfortunately only german) article by an austrian webpage
associated with the cochrane collaboration (i.e. that should be considered a
relatively trustworthy source) that explains this difference due to the fact
that the BMJ metaanalysis included many low quality studies that were excluded
in the other metaanalysis. This is an indication that this is might be not a
real effect, but an artifact of the low quality evidence this analysis is
based on.

tl;dr I won't buy Vitamin D supplements.

[1]
[https://journals.plos.org/plosone/article?id=10.1371/journal...](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0162996)

[2] [https://www.medizin-transparent.at/vitamin-d-und-das-
immunsy...](https://www.medizin-transparent.at/vitamin-d-und-das-immunsystem-
was-stimmt/#ref1)

~~~
stjohnswarts
You don't need vit D if your blood levels are not low, but vitamin d
supplements absolutely can raise it if it is low, there is not arguing with
that fact. It's established science.

------
eyeball
What’s the connection between calcium and D?

I recall someone telling me you had to be careful of supplementing D or you
could promote calcification in arteries. You had to take with a calcium shop
or something. Is that true?

~~~
leto_ii
_Vitamin D has a significant role in calcium homeostasis and metabolism. Its
discovery was due to effort to find the dietary substance lacking in children
with rickets (the childhood form of osteomalacia).[12] Vitamin D supplements
are given to treat or to prevent osteomalacia and rickets._

taken from the Wikipedia article:
[https://en.wikipedia.org/wiki/Vitamin_D](https://en.wikipedia.org/wiki/Vitamin_D)

------
durpleDrank
[https://www.grc.com/health/vitamin-d.htm](https://www.grc.com/health/vitamin-d.htm)

------
ehnto
Interesting! Anecdotally I used to get very, very bad respiratory infections
once a year when working in an office full time, getting at best an hour in
the sun a day. Now I remote work and get anywhere from 2-6 hours sun most
days, and I haven't had a serious infection for more than a year and a half.
Could still be coming, but I feel 200% better overall so regardless, highly
recommend getting outside more.

Edit: maybe this came off as a humble brag? Getting a downvote or two, which I
don't mind, but I wouldn't want to give off the wrong impression. I only work
from home, I am not a jetsetting nomad, I can just work around my outdoor
activities now.

~~~
jgrahamc
Sounds like your exposure to other people might have changed dramatically:
working in an office full time -> remote work.

~~~
arkitaip
Probably. Or maybe a less stressful commute to work, no crazy office politics,
a change in diet/exercise (because you now have time to do those things
properly)... It's really difficult to accurately establish correlation let
alone causality when it comes to changes in one's health.

~~~
ehnto
Definitely! So many things changed when I went remote that I would never
suggest it's entirely down to sun exposure. It would be impossible to say
definitively.

------
open-source-ux
In the UK, a science advisory body (Scientific Advisory Committee on
Nutrition) published a review of the evidence on vitamin D and health in 2016.
Their recommendation: adults and children over one in the UK should take
vitamin D supplements in winter.

This advice may not be applicable to people living in sunnier climes. Here is
an overview of the guidelines on the NHS website which includes a link to the
300 page scientific review.

[https://www.nhs.uk/news/food-and-diet/the-new-guidelines-
on-...](https://www.nhs.uk/news/food-and-diet/the-new-guidelines-on-vitamin-d-
what-you-need-to-know/)

------
appstorelottery
Unfortunately I can't find the source, but I read somewhere that it wasn't
proven that Vitamin D supplements can improve outcomes after infection has
occurred. Can anyone find the source on this and verify?

~~~
Spacemolte
I unfortunately can't find the source either, but I read something about you
having to take vitamin D suppliments for a while before the change could be
detected in the body, ie. if you are already sick it does not matter to take
suppliments where you only see the benefit after weeks or months. This seems
to support what you read.

------
_cairn
I had my Vitamin D levels tested last year, was enlightening. For those
interested it's a pretty painless (small blood sample) and inexpensive test.

~~~
brokensegue
I was recently charged several hundred for a vit D test. The price is
basically random in the US.

~~~
stjohnswarts
That's insane, my whole panel for vitamin d, some other vitamins, insulin
levels, immune analysis, etc all are about $120 when I do my annual checkup.

~~~
brokensegue
Yeah insurance decided not to cover it for some reason even though my doctor
ordered the test. The rest of the panel was a few bucks after insurance.

------
officialchicken
Can any physicians or researchers here verify the credibility of this site, to
prevent misinformation?

~~~
pacman83
British Medical Journal? Impact factor 27.604 in 2018. But in scientific
publishing the intended audience is not lay people. You really have to know
how to read the articles to determine what they mean. I liked their series of
articles called "How to Read a Paper."[0] But keep in mind [1].

0\. [https://www.bmj.com/about-bmj/resources-
readers/publications...](https://www.bmj.com/about-bmj/resources-
readers/publications/how-read-paper)

1\.
[https://journals.plos.org/plosmedicine/article?id=10.1371/jo...](https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124)

~~~
officialchicken
Thank you, HN is definitely not the intended audience

------
glaugh
I found this to be a useful summary of similar research:
[https://examine.com/nutrition/supplements-for-cold-and-
flu/](https://examine.com/nutrition/supplements-for-cold-and-flu/)

------
mc32
So cold viruses do better in cold weather and in northern latitudes with fewer
sunlight hours we may expect the combination to result in more cold in winter
time?

------
beagle3
n=1: 10,000 IU of vit D3 before 10am significantly improves my sleep. Gwern
has some of his own relevant n=1 experiments described on his site.

------
MrK93
I already take vitamin D for weightlifting, I guess I'm covered. Many
advantages also for hormones.

