Living with diabetes blog

Caffeine and blood sugar: What's the connection?

By Nancy Klobassa Davidson, R.N. and Peggy Moreland, R.N., C.D.E. February 3, 2010

I love coffee; it's one of my favorite vices. The sight and smell of a cup of freshly brewed, rich, dark brown liquid java, first thing in the morning, is a sight to behold. Other than the caffeine, coffee seems like a pretty benign beverage. In fact, I've been hearing a lot of good things about it lately.

A large observational study recently found that people who drink coffee appear to have a reduced risk of developing type 2 diabetes. An article in Diabetes Self-Management relates this reduced risk of developing type 2 diabetes to the possibility of antioxidants in coffee.

In visiting with some patients, they say coffee causes their blood glucose to rise. That doesn't make any sense to me at first, because coffee without cream/sugar doesn't have any carbohydrates or calories.

"Caffeine impairs insulin action but not glucose levels in young, healthy adults, but people with type 2 diabetes may experience a small rise particularly after meals," says Dr. Maria Collazo-Clavell, a Mayo Clinic endocrinologist. The amount of caffeine that causes this effect is about 250 milligrams — or the equivalent of 2 to 2 1/2 cups (473 to 591 milliliters) of plain, brewed coffee — a day.

Twenty years ago, a serving of coffee was 1 cup. Today, it's often 2 cups. Maybe we don't need to cut coffee completely out of our daily routine, just pay a little more attention to portions.

Doesn't it seem like about the only thing that doesn't affect your blood glucose is water?

Does anyone remember Mrs. Olsen from the 70's coffee commercials? I wonder if she had type 2 diabetes.

Please share whether caffeine affects your blood glucose.

Have a great week.



Feb. 03, 2010