Speculation on additional sources of vitamin D: UVC, Xray, plants

Where Is the Missing 40 μg/d of Vitamin D?

doi: 10.3945/​jn.113.178780 J. Nutr. September 1, 2013 vol. 143 no. 9 1520

by Dr. Cannell

UVC was proven to generate vitamin D 70 years ago

Following is an image of PDF which is behind a paywall – so the text cannot be translated.

See also VitaminDWiki

• UVA decreased serum levels of vitamin D - RCT Oct 2012 another possible reason: could have had higher UVB/UVA ratio than normal

• UVB produced 8X more vitamin D as solar UV – July 2012

• Vitamin D3 for Vegans - many studies D3 made from Lichen, marine algae, mushrooms

• Vitamin D from animal increases 6X when consider that already processed by animal livers