Dr. Ryan Neuhofel explains the Hemoglobin A1c lab test and why it is so important when monitoring diabetes.

FORBES: Doctors as Teachers

Hemoglobin A1C (also called HgA1C or A1C) is a measure of glycated hemoglobin.

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The average hemoglobin A1C level was higher (meaning less than optimal control) in patients with the most severe vitamin D deficiencies.

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