Fast Five Quiz: Can You Identify and Prevent Vitamin D Insufficiency?

George T. Griffing, MD


June 04, 2014

A 25(OH)D level of less than 32 ng/mL is considered vitamin D insufficient. A 25(OH)D level of less than 20 ng/mL has been used to define vitamin D deficiency. Intestinal calcium absorption is optimized at levels of more than 32 ng/mL. Parathyroid hormone levels start to rise at 25(OH)D levels less than 31 ng/mL, which is another marker for vitamin D insufficiency.

For more on the workup of vitamin D deficiency, read here.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.