How fast is fast?

roller-coaster-365770_640Have you ever felt a little low, only to check your blood sugar, and it is Ok?

I have always thought that this was due to a rapid drop in blood sugar levels. But that started me thinking – exactly how fast is fast? In other words, how fast must BG levels drop to start feeling this way?

Is this feeling really due to a rapid drop in BG’s? Or could it be something else, perhaps some intricate balance between blood sugar levels and insulin levels? The body is an amazing machine. The mechanisms that manage blood sugars for people without diabetes are astounding. So maybe there’s more to it than just the dropping BG.

What do you do when you feel this way?

I’m at 142 mg/dL, about 2.5 hours post-meal. That’s good. But I feel “funny” – like I’m low. But 142 mg/dL is not low. The symptoms are so very slight. 8 minutes later, I do another test. 137 mg/dL. Is it really going down, or could that difference be the variance you will find in any two blood sugar checks? If it is really going down, how far will it go?

That depends on how much of that last bolus is still working to lower the blood sugar. I have my insulin duration set to what many people will think is too long. I’ve got it set to 5:30. Yes, that’s right. 5 hours and 30 minutes. I don’t want to go too off-topic on this post, so maybe I’ll address that subject at another time in another post.

3 hours post-meal, and I’m at 127 mg/dL—still a little less than 3 units on board. However, I know that it’s mostly the “tail” of that insulin, which has much less impact on my blood sugar.

Still feeling a little off, but I notice that it’s subsiding a bit. Or maybe I’m just getting used to it? Time will tell.

I want to stress that I am in a situation where I can keep a very close eye on things. If the scenario were a bit different, I might choose to pop a couple of glucose tabs and be 100% sure that I won’t go low.

4 hours post-meal, and I’m at 91 mg/dL. It would be good if the BG descent stops here.

4.5 hours post-meal, and I’m at 74 mg/dL with 1.07 units of residual lunch bolus (again, almost all “tail,” though).

At this point, I’m ending the experiment and having 4 glucose tabs. I’m not comfortable being in the 70’s, and I also need to walk up to the service station to pick up my beat-up old truck, so I need a little boost for that walk.

But why did I start feeling off with a blood sugar of 142? That is the point. There must be more to the equation than just hitting a key number that kicks off the symptoms of low blood sugar, however slight those symptoms might be.

To summarize my BG’s all in one easy to read place:

1:48 – 142 mg/dL – started feeling slight symptoms of low BG.
1:56 – 137 mg/dL
2:30 – 127 mg/dL
3:30 – 91 mg/dL
4:00 – 74 mg/dL – end of test – ate glucose tabs.

Is the drop I experienced this afternoon fast enough to be considered “rapid,” and could it be that “rapid” change that made me experience the symptoms? I don’t know. I have had one other experience that says otherwise. Was it a fluke? Who knows. That experience is an interesting one, and you can read about it here.

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Scott K. Johnson

Patient voice, speaker, writer, advocate, and Senior Community Manager at Blue Circle Health. Living life with diabetes and telling my story. All opinions expressed are my own and do not necessarily represent my employer’s position. Read more…

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