(1) Dr. John Campbell dedicates yet another video to vitamin D, in which he also looks at two large-scale Israeli studies
The first, by Frenkel-Morgenstern and coworkers, I have covered here before:
The second is so far only a preprint, but looks quite promising. It was carried out by a team led by Dr. Ariel Israel from the research division of Clalit Health Services (the country’s largest HMO).
METHODS We carried out a population-based study among 4.6 million members of Clalit Health Services (CHS). We collected results from vitamin D tests performed between 2010 and 2019 and used weighted linear regression to assess the relationship between prevalence of vitamin D deficiency and Covid-19 incidence in 200 localities. Additionally, we matched 52,405 infected patients with 524,050 control individuals of the same sex, age, geographical region and used conditional logistic regression to assess the relationship between baseline vitamin D levels, acquisition of vitamin D supplements in the last 4 months, and positive Covid-19. RESULTS We observe a highly significant correlation between prevalence of vitamin D deficiency and Covid-19 incidence, and between female-to-male ratio for severe vitamin D deficiency and female-to-male ratio for Covid-19 incidence in localities (P<0.001). In the matched cohort, we found a significant association between low vitamin D levels and the risk of Covid-19, with the highest risk observed for severe vitamin D deficiency. A significant protective effect was observed for members who acquired liquid vitamin D formulations (drops) in the last 4 months.p<0.001 means: less than one chance in a thousand that the different results in the two groups were due to coincidence
Just how prevalent is vitamin D deficiency really in sunny Israel? Table 2 from the preprint: look at the percentages for the first row (less than 30 nanomol per liter). As you can see, it’s relatively rare among the general population, more common in the chareidi (“ultra-Orthodox”) sector, where more of life is spent indoors and both men and women cover most of their skin for reasons of “tzniut” (modesty) — and very common among Arab women (2.6 times more than their male counterparts)…
Dr. Campbell mentions something I’ve discussed here previously: counterintuitively, the problem is much less common in Scandinavia countries than in, say, Spain or Northern Italy. Quite simply: Scandinavians know they will get in trouble in winter unless they fortify their diet with vitamin D (I don’t think I’ll ever forget seeing a bottle of cod liver oil and shot glasses at a breakfast buffet in northern Norway). Northern Italians and Spaniards get enough in summer but falsely assume they won’t need any supplements in winter…
(2) Wendover Productions, a YouTube channel focusing mostly on logistics and the airline industry, has a new video looking at some of the logistical complexities of massive vaccine distribution on a short time scale:
(3) Breaking news: Israel is tightening its lockdown. More details as they develop.