1. Chronic kidney disease and vitamin D: how much is adequate?
Marco Ruggiero, Stefania Pacini 
Kidney International 
Volume 76, Issue 9, Pages (November 2009)
DOI: /ki
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2. Figure 1
Vitamin D and tortoises. Vitamin D3 is considered safe at about 100IU/kg/wk in reptiles such as these tortoises (from the 89th plate of Ernst Haeckel's Kunstformen der Natur (1904), depicting organisms classified as Chelonia). In humans, however, the adequate amount of vitamin D supplementation has yet to be determined.
Kidney International  , DOI: ( /ki )
Copyright © 2009 International Society of Nephrology Terms and Conditions