Vitamin D calms immune overreaction
When vitamin D is low, immune systems are hyperactive, according to findings from data doctors analyzed in 10 countries, after noticing differing death rates between them. Before the study, theories included variability in healthcare quality, differences in population age distribution, lower or higher Covid-19 testing rates, or different strains of the virus.
None of these turned out to play a significant role. Instead, doctors found a strong correlation between vitamin D levels and the “cytokine storm,” a hyper-inflammatory condition caused by an overactive acquired immune system, which can severely damage lungs.
“This is what seems to kill a majority of Covid-19 patients, not the destruction of the lungs by the virus itself, but complications from a misfiring immune system.” The reason children are less likely to die, doctors said, may be a less fully developed acquired immune system, which is more likely to overreact, as the second line of defense, after the innate immune system.
Reference: BMJ Yale; May, 2020, Vol. 4, 20058578, Published Online
Regional selenium soil levels are key
Because viral infections historically have a link to selenium deficiency, doctors wondered if Covid-19 infections might correlate with the belt of selenium-deficient soils that runs northeast to southwest in China.
In preliminary findings using data collected in February, 2020, doctors saw areas with high levels of selenium were more likely to recover from the virus. For example, Enshi, in Hubei province, has the highest selenium intake in China, and had a Covid-19 cure rate three times higher than the average city in the province.
Reference: American Journal of Clinical Nutrition; 2020, Vol. 111, No. 6, 1297-9