Is an HbA1c of 6.8 Good Enough?

What the number measures ▶ 1:11

HbA1c, or A1c, is the share of hemoglobin, the oxygen carrier in red blood cells, that has sugar stuck to it. More sugar in the blood over time means a higher share. Red cells last a few months, so A1c reflects roughly the past two to three months, weighted toward recent weeks.

Targets, and who sets yours ▶ 1:35

There's no single number every group agrees on. Diabetes Canada says 7 or below for most; a U.S. health institute, below 7 for many. The American College of Physicians suggests 7 to 8 for most. Korea's diabetes association, below 6.5. And all say to personalize it.

So how do clinicians personalize it? Some guidelines suggest tighter goals for some people early in diabetes, if reachable without low blood sugar. Looser goals may suit people with severe lows, limited life expectancy, serious illnesses or long-standing, hard-to-control diabetes. Preferences, treatment burden, your medicines and other conditions count too.

Why not aim lower? In the UKPDS trial, tighter control from diagnosis paid off slowly, with slightly fewer heart attacks and deaths. But in the ACCORD trial, aiming below 6 in people starting at 7.5 or higher, with about ten years of diabetes and high heart risk, was stopped early: over three and a half years, 5 in 100 died versus 4, cause unclear, and serious lows tripled.

Medicines matter too. On its own, metformin rarely causes low blood sugar, its label says, though it can happen if you don't eat enough, drink alcohol, or take other diabetes medicines. Insulin and diabetes pills called sulfonylureas carry more risk. Some guidelines allow lower goals only if reached safely, a call made with your clinician.

What one result can tell you ▶ 3:12

One result can't show a trend, and tests vary. A U.S. government health page happens to use 6.8 as its example: a repeat test on the same sample could read from about 6.4 to 7.2, a range it says used to be wider. And conditions like iron-deficiency anemia, kidney failure or recent blood loss can skew A1c.

And the new routine? Our listener started gym visits and evening walks three to six months ago. In trials, where people started near 7.7 on average, structured exercise, including walking programs, lowered A1c by about half a point. That's an average, not a prediction. By our arithmetic, a July test came anywhere from just before the routine to a few months in, so alone it can't show what exercise did; a later result will say more.

Keeping it up is the hard part. In the Look AHEAD weight-loss trial, fewer than 1 in 3 people met its strict activity goal after a year. Ongoing counseling, supervised sessions and step goals have modest, mixed support.

So 6.8 is under 7, a common general goal, but your goal is personal. Questions for your clinician: What goal fits me, and why? When should we recheck, and what change would matter? Could anything skew my result? And does my treatment carry any risk of low blood sugar, including with exercise?