Immune boosting Nutrition and practices

I do not know if anyone has seen this (apologies if it has been posted before), but there has been research about the link between vitamin D and Corona fatalities. This was publicized in a Dutch newspaper today, so that link won't help much, but there has been documentation in English as well.

It basically said that the elderly are more likely to be deficient in Vitamin D, because the skin doesn't take it in from the sun as it used to. In the southern (European) countries, where there is a lot of sun, the elderly usually shy away from it more because it is hotter there. People with a darker skin are also more likely to be deficient. 

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