[mindviews]

Here's the paper mentioned in (a) above that's the source of the claim: [1] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3585561

Here is another paper with similarly stark data: [2] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3571484

Table 1 in each of those papers show Vitamin D status vs Outcomes. The correlation between Vitamin D status, where Normal is >30 ng/ml (or 75 nmol/L), and death rates is stark.

From [1] (which had n=780 cases) here is the punchline: "98.9% of Vitamin D deficient cases died while only 1.1% of them were active cases. 87.8% of Vitamin D insufficient cases died while only 12.2% of them were active cases. Only 4.1% of cases with normal Vitamin D levels died while 95.9% of them were active cases."

From [2] (which had n=212 cases) here is the punchline: "Of the 212 (100.0%) cases of Covid-2019, 49 (23.1%) were identified mild, 59 (27.8%) were ordinary, 56 (26.4%) were severe, and 48 (22.6%) were critical (Table 1). Mean serum 25(OH)D level was 23.8 ng/ml. Serum 25(OH)D level of cases with mild outcome was 31.2 ng/ml, 27.4 ng/ml for ordinary, 21.2 ng/ml for severe, and 17.1 ng/ml for critical."

Note: the classification for outcomes was "(1) mild – mild clinical features without pneumonia diagnosis, (2) ordinary – confirmed pneumonia in chest computer tomography with fever and other respiratory symptoms, (3) severe – hypoxia (at most 93% oxygen saturation) and respiratory distress or abnormal blood gas analysis results (PaCO2 >50 mm Hg or PaO2 < 0 mm Hg), and (4) critical – respiratory failure requiring intensive case monitoring."

I want to see a dozen more studies like [1] and [2] to see if this holds up to replication.

The show notes for the parent video are quite comprehensive with links to references. The summary above leaves out the detailed discussion of the interplay between Vitamin D, the renin-angiotensin-system, the ACE2 receptor, and SARS-CoV-2: [3] https://www.foundmyfitness.com/episodes/vitamin-d-covid-19

[disgruntledphd2]

Thanks for the links!

Interestingly, these papers together are much stronger evidence than either apart. This is because they use different methods. The OP is a population level study, while the second link you shared is a retrospective individual level study.

While I have some concerns with the stats in both papers (I'm always suspicious of p-values close to the magic number of 0.05), this does seem like interesting research, and potentially very helpful to dealing with Covid-19.

The irony of course, is that I suspect many of the Northern latitude people with high levels of Vit-D may be getting it through tourism to Southern Europe, which is very unlikely to happen this year.

[anpago]

If you live in a country with little daylight for part of the year your going to consider supplements of Vitamin d.

Also pickled herring is a delicacy in the many countries which have fared well in Europe in the fight against covid 19.

Also oily fish like salmon and mackerel are good for vitamin D.

Yet for many Brits it's a fish we rarely consider but is one of the biggest Concerns about the UK denying access to EU nation's to certain waters I believe with Brexit.

https://en.m.wikipedia.org/wiki/Herring_as_food

https://en.m.wikipedia.org/wiki/Pickled_herring

[nradov]

A brief vacation to southern Europe won't give a Scandanavian enough stored Vitamin D to last the rest of the year. Supplement use is common, and they tend to eat a lot of Vitamin D rich foods.