Diabetes care is about to get a little simpler. Doctors are going to start providing patients with a new health number, in addition to the A1C, which actually sounds like what it is: the estimated average glucose, or eAG. It has units that look familiar to anyone who has ever taken a blood glucose reading: mg/dl (or mmol/l, the international version).

The A1C, a blood test that gives a snapshot of blood glucose control over the past few months, is a terrific tool for estimating the risk of long-term diabetes complications and tailoring treatment. Yet there is something unsatisfying about the A1C—for patients, who may often wonder “7 percent of what exactly?” and for providers, who have the burden of explaining it. But exactly how A1Cs correspond to real average blood glucoses had never been adequately tested, until now.

A large international study, published in the August issue of the journal Diabetes Care, followed 500 people—some with type 1 or type 2 diabetes and some without diabetes—for three months, testing each person’s blood glucose an average of about 2,700 times. Then, the researchers averaged all of these readings and compared them to the participants’ A1Cs, finding a strong correlation between the average glucose and A1C. For example, the study found that people with an A1C of 7 percent have an eAG of approximately 154 mg/dl.

Although laboratories will in fact continue to be measuring the A1C, they will soon be giving results as eAG numbers, too.

A1C (%)     eAG (mg/dl)