Consultant Physician, medical researcher and author, Dr David Grimes conducted much original research on the essential to life Vitamin D. Buy his inexpensive latest book here. https://yorkbookshop.com/health-and-personal-development/307-vitamin-d-deficiency-and-covid-19-its-central-role-in-a-world-pandemic.html
2 minor corrections – 150nmol/L = 60ng/mL (not 80ng/mL as stated and at 2min 27secs)
57min 11 secs Calcifidiol appears in the BNF here:
https://bnf.nice.org.uk/drugs/calcifediol-monohydrate/
and medicinal form here
https://bnf.nice.org.uk/drugs/calcifediol-monohydrate/medicinal-forms/
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