Vitamin D deficiency and insufficiency among US adults: prevalence, predictors and clinical implications https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/vitamin-d-deficiency-and-insufficiency-among-us-adults-prevalence-predictors-and-clinical-implications/44E436843510FE6BDE856D5BCB9C651F (University of Michigan School of Medicine, 2018) Vitamin D deficiency (VDD) and insufficiency (VDI) are increasing at a global level Serum 25-hydroxyvitamin D (25(OH)D) measurements were…