Low Levels Of Vitamin D Cause Problems For Acutely Ill Patients 5/10/2009   A group of endocrinologists in Sydney have observed that very sick patients tend to have very low levels of Vitamin D. The sicker they are, the lower the levels. Dr Paul Lee, Professor John Eisman and Associate Professor Jackie Center, researchers at Sydney's Garvan Institute of Medical Research, examined a cohort of 42 Intensive Care Unit (ICU) patients. Forty-five percent turned out to be Vitamin D deficient. Refrence