New Time to Test Glucose Levels

If your blood glucose is under good control, it’s still better to check it after meals rather than before breakfast, as I wrote here recently. But new research presented at the American Diabetes Association's 66th Scientific Sessions that I just attended in Washington indicates that it might make sense to check your blood glucose levels sooner after eating than we previously thought.

Both the American Diabetes Association and the American Association of Clinical Endocrinologists have said that its best to check our levels two hours after the first bite of a meal. They haven’t changed that recommendation yet and they might not change it. But we know now that people with either type 1 or type 2 diabetes reach a peak 72 minutes after eating with a variation of 23 minutes either way.

Dr. Sandrine Daenen from Paris, France, and four associates made “Use of the CGMS To Assess the Optimal Time to Measure Postprandial Glucose” and presented their findings on June 10 in their oral presentation 70-OR. The CGMS is Medtronic MiniMed’s first continuous glucose monitoring system.

A study by German researchers last year found that pregnant women with diabetes reached peak blood glucose levels 74 minutes after a meal. Until now, that was the only study that tried to measure when people with diabetes following their usual diet reach peak glucose levels.

Knowing when we peak is especially important for people with either type 1 or type 2 diabetes who use rapid-acting insulin. If the peak is too high 74 minutes after starting a meal – 140 mg/dl (7.8 mmol/l) to 180 mgl/dl (10 mmol/l) depending on whose recommendations you follow – you can take corrective action sooner than the official recommendations.

Learn more about managing type 1 and type 2 diabetes.