What Makes My Blood Glucose Go Up...And Down?

Wearing my new Guardian REAL-Time continuous glucose monitor continues to give me a lot more help in controlling my glucose levels than I ever expected. Few people who don’t have type 1 diabetes have used continuous monitors until recently. Most of the people with type 2 who have been using them take insulin, which makes glucose control critical.

But I have type 2, don’t use insulin, and have tight control. So I didn’t expect to learn much about my levels from the Guardian REAL-Time.

Still, the lessons keep coming. A couple of days ago I had my normal low-glycemic breakfast of hullless barley and nothing more until I went off to an early afternoon appointment to get my hair cut. My barber always has those miniature chocolate bars and I have always eaten some.

As much as I love chocolate, and probably because I love it so much, I don’t keep any at home in order to avoid temptation. I do eat this guilty snacks sometimes when I’m out, thinking that I can control myself, particularly when other people can see how much I grab.

But since I was pretty hungry, I ate a total of six of them before and after my haircut. Then, I checked the continuous monitor and was surprised that in just a few minutes my glucose level had shot up 40 or 50 points. That will teach me.

Yesterday I got an even bigger lesson about the value of a continuous monitor. Out about town running a bunch of errands, I noticed that the Guardian REAL-Time was reporting a steadily increasing glucose level all morning. I hadn’t eaten anything since a 9 a.m. breakfast (of hulless barley again) and here it was almost 2 p.m. Still, my level climbed, reaching 180 mg/dl (10 mmol/L).

That’s far too high, and I knew I had to take action. Since I don’t use insulin, there is only one thing that I know that will bring down my level quickly. Exercise.

So, like a wild man on the streets of Boulder, I literally ran between all my errands at different stores. Soon, my levels dropped to a level that made me more comfortable.

A few hours later when I got home (where I had left my fingerstick glucose meter), I compared its readings with that of the continuous monitor. This is something you need to do regularly. It’s in accordance with President Reagan’s philosophy of “trust, but verify.” By this point the Guardian REAL-Time said my level was down to 126 mg/dl (7 mmol/L), and my meter, the AgaMatrix KeyNote, reported that it was 117 (6.5 mmol/L). That was a lot better, but the 9 point difference then indicates that I had really gone high earlier this afternoon. I recalibrated the Guardian REAL-Time.

The third thing I wanted to do was to try to figure out why my level had gone so high. I frankly couldn’t think of a better resource than the book What Makes My Blood Glucose Go Up…and Down? in the “New Glucose Revolution” series that Marlowe and Company publishes.

I had to refer to the book, even though I wrote one-third of it myself. Kaye Foster-Powell, an Australian dietitian, and I wrote it together with Dr. Jennie Brand-Miller, the world’s leading expert on the glycemic index.