HemoglobinA1c (HbA1c) has been touted as one of the most important blood tests you can get. It reveals how well you’re controlling your blood sugar. Some experts recommend that you strive to get your HbA1c as low as possible—5.0 or less. But health authorities recently issued new guidelines arguing for leniency in HbA1c targets. Which is it? How do we reconcile these opposing viewpoints? What does HbA1c actually measure? Why does it offer a “window” into all the cells in your body? Why do doctors sometimes ignore borderline HbA1cs? Why could that be detrimental to patients? What are some of the sources of inaccuracy in HbA1c? What other tests shed light on HbA1c results? Which nutraceutical has been shown to improve HbA1c?