[martingoodson]

In case you weren't aware, controlled trials have shown that vitamin d supplementation protects against respiratory disease [1]. This is evidence that the association you highlight is more than a spurious correlation.

It's likely to be causal.

[1] https://www.bmj.com/content/356/bmj.i6583

[lrpublic]

Updated NHS advice on vitamin D from [1]

“ Coronavirus update Consider taking 10 micrograms of vitamin D a day to keep your bones and muscles healthy.

This is because you may not be getting enough vitamin D from sunlight if you’re indoors most of the day.

There have been some news reports about vitamin D reducing the risk of coronavirus. However, there is no evidence that this is the case.”

[1] https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-...

[roenxi]

NHS may say 'no evidence' - but it seems likely what they mean is that nobody has done a vitamin D-coronavirus trial. So it isn't that there is no evidence but rather the evidence is not overwhelming.

"No evidence" makes it sound like there is actually no evidence. There is evidence - it just got linked in the two comments that make up the root of this thread.

[mistermann]

A good example of why trust the science (among other things) with no knowledge of epistemology is dangerous.

[DanBC]

See also this: https://www.sciencedirect.com/science/article/pii/S187140212...

> COVID-19 appears to disproportionately affects black and minority ethnic individuals. The underlying mechanism is unknown.

> One potential mediator could be their higher prevalence of apparent vitamin D deficiency.

> We explored whether blood 25 hydroxyvitamin D (25(OH)D) concentration was associated with COVID-19 risk.

> We found no evidence that (25(OH)D) explains susceptibility to COVID-19 infection, either overall or between ethnic groups.

[martingoodson]

It's worth noting that this study only looked at risk of infection, not the severity of infection. The grandparent comment was about severity/death.

[drak0n1c]

If it's true that Vitamin D is such a large factor in reducing the lethality of respiratory disease -- perhaps it's better to loosen lockdown rules to ensure the wider population can get more sun before they inevitably catch the virus.

It may explain why heavily indoors NYC had so many lethal cases, even as most infected were already keeping themselves indoors.

[simonh]

If the extra time out from loosening was all spent out in the sunshine, maybe it might just balance out the increase in cases, but there’s no way that’s what would happen. To make a significant difference requires an extra several hours a day out in sunshine. Better to just advise people to take supplements.

[elorant]

But what about Spain? A Mediterranean country with lots and lots of sunshine.

[AQuantized]

Sunnier countries can still have large vitamin D deficient populations. I read a study regarding the correlation between mental illness and vitamin D deficiency a few years ago, and Italian patients were still often very deficient. If people don't go out in the sun enough, or wear too much sun cream, it doesn't matter how sunny it is.

[whiddershins]

Also worth noting that Europe in general is really far north compared to the US. Spain is on the same latitude more or less as NYC.

[spiralx]

That's misleading because Europe is on the western edge of the Eurasian landmass, meaning it gets the benefit of warm air heated up over the ocean. By the time the air gets to the eastern edge of a landmass it's a lot colder, which is why London has a milder average temperature than NY and Vladivostok, despite being almost 10° further north than both.

[whiddershins]

Yes, but vitamin D production relates to direct sunlight ... I think the angle of the sun and amount of atmosphere it has to go through affects UV amounts so a warmer European country does have less direct sun therefor more potential for vitamin D deficiency ...

TBH I am not super solid on every one of these details.

[ejanus]

But it has slower transmission in Africa and low mortality.. This is getting hard to factor...

[joemazerino]

Vitamin D deficiency can still occur in sunny countries. To get the adequate amount of Sun from Vitamin D takes a day out in the sun entirely as opposed to basic supplementation.

[jansan]

It may also explain why every year Corona Virus related infections appear in November and end in May.[1]

Also, SARS 1 ended at the beginning of June 2002. There is clearly a correlation that needs to be looked into.[2]

[1] https://www.medscape.com/answers/302460-86798/what-are-the-s...

[2] https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndr...

[m463]

A friend of mine had cancer and they had him taking D3 immediately.

also I was out shopping recently and they seemed to sell many varieties of D3, but I didn't see any other D vitamins offered for sale. Is D deficiency really D3 deficiency? or have the other D vitamins sold out?

[leto_ii]

The way I understood it, D3 is the easiest one to absorb. Both D2 and D3 do the same thing, but their efficiency is different.

[vixen99]

https://vitamindwiki.com/ is a useful aggregate site for papers (peer-reviewed and others) on vitamin D. The latter is cholecalciferol (https://en.wikipedia.org/wiki/Cholecalciferol).

https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessiona... (excellent series for all vitamins)

Different manufacturers = varieties? It's the same stuff or should be.

[odrekf]

As a vegan, I learned that there's D2 (comes from plants) and D3 (comes from animals), and they are the same as far as I know. Not sure about using them for treatments.

[irishcoffee]

As a carnivore I’ve learned the same.

[oarsinsync]

As an omnivore I didn’t know either of these things before now, so I thank my learned extreme-dieted colleagues for sharing.

[Throwawayaerlei]

> A friend of mine had cancer and they had him taking D3 immediately.

The last thing in the world a cancer patient needs is well nourished cancer cells, most grow and reproduce quickly.

[Zach_the_Lizard]

There is some evidence that vitamin D deficiency is associated with prostate cancer: https://clincancerres.aacrjournals.org/content/20/9/2289.abs...

There are a number of other studies on this. From what little I've read, if the effect is real,it seems the it is relatively weak, but still worth doing.