Vitamin D needs in 2004:1000 IU, 10 years later same author says 3,500 IU
Back in 2004 Dr. Holick said that 1,000 IU and 10 minutes of sun was enough to get all of the benefits from Vitamin D
10,600 publications with Vitamin D in the title were published between Jan 2005 and May 2014
Dr. Holick update in Jan 2014 - need 50,000 IU biweekly = 3500/day
So, instead of #F00:10 minutes to get 1,000 IU, you may need 35 minutes to get 3,500 IU if you are
AND young
AND not obese
AND have light skin, without suntan
AND it is summer
AND it is the middle of the day
AND you have lots of skin exposed to the sun
AND you are lying down
AND you are not wearing sunscreen.
And much more time otherwise
3X senior
3X obese
5X black skin
XX winter if far from equator
"And it would require nearly constant exposure to sunlight to reach the levels he (Dr. Holick) recommends"
Why Are So Many People Popping Vitamin D? NYT April 2017
* Vitamin D supplementation guidelines (adults – 50,000 IU per week) – Feb 2017 Co-authored by Dr. Holick