You can see the development of the UK guidance. There's a consensus statement from 2010, here: https://www.nhs.uk/Livewell/Summerhealth/Documents/Concensus_sta

You can see the development of the UK guidance. There's a consensus statement from 2010, here: https://www.nhs.uk/Livewell/Summerhealth/Documents/Concensus_statement%20_vitd_Dec_2010.pdf https://www.nhs.uk/Livewell/Summerhealth/Documents/Concensus... And there's discussion of the new guidelines (with links to the newer research) here: https://www.nhs.uk/news/food-and-diet/the-new-guidelines-on-vitamin-d-what-you-need-to-know/ https://www.nhs.uk/news/food-and-diet/the-new-guidelines-on-...