https://youtu.be/zy-jEXIxpSo?t=649
eric berger says that there is a thing called "vitamin D resistance"
.... which is like "insulin resistance" ... you might have good levels
of insulin or vit D circulating in your blood ... but if it does not
get into your cells, then you have an issue
your level of Vitamin D resistance can be measured by a parathyroid
test ... he explains here on the tape ... if your uptake of Vit D is
good, then your parathyroid levels go down
I dont think that he explains how to get a good uptake of Vit D other
than doing megadoses of Vitamin D
per comment ... everyone needs 100 mcg of Vitamin K2 for every 1K of Vit D taken