What is a ‘normal’ glucose level?

Dear Dr. Roach: All my friends who are hypertensive have been able to bring their blood pressure to or less. However, I have diabetic friends who are taking several diabetic drugs but none has been able to bring the fasting glucose levels to the ideal amount, around 85. Is this common? Why is it so hard to lower? — R.I.

The “ideal” level for neither blood pressure nor blood sugar is known for certain. The consensus opinion for the best goal has changed over time, depends on a person’s situation.

There is indeed increasing evidence that blood pressure should be in the low range of 120⁄80. The medications we have now are very effective at getting the blood pressure down, with a low risk of side effects.

Diabetes control can be measured by fasting glucose, but a better predictor of diabetes complications is the hemoglobin A1C. It is affected by both fasting and non-fasting glucose, and looks at overall blood sugars over the preceding weeks to months.

The A1C level in a person without diabetes is normally between 4% and 5.6%. That’s an AVERAGE blood sugar of 70 to 126 mg/dL. However, it’s not recommended for most older Type 2 diabetics. Part of the reason is that people with an A1C that low are at risk for having so low a blood glucose that they can develop symptoms of hypoglycemia.

Another part of the reason that many people with diabetes are recommended an A1C level closer to 7% is the result of the ACCORD study. It showed that people with diabetes who are at high risk for heart disease were more likely to suffer a heart attack. So, the idea that there is an ideal fasting blood sugar goal is oversimplified.

Many people with Type 2 diabetes will have a much easier time getting blood sugars near normal with weight loss, especially if they lose weight early in the course of the disease.