Can You Guess Your BG Before Using Your Meter?

recently i was put to the test. it was about being in touch with my body and how i might know where my BGs are at any given time without using a finger stick or a CGM.

i am familiar with how i feel when i am crashing. i know the symptoms of each level of my lows. for example: when i am getting into my 60s, i feel a little light headed, but not terribly so. when i get into my 50s, i start to shake and i will see bright lights and spots before my eyes; i cannot even read my meter without help. when i am below, in my 40s or even 30s, i am shaking all over and cannot make a sober decision for myself (what do i eat? what do i drink? ) i must rely on the kindness of my husband to pour juice down my throat…otherwise, i will just open up the fridge and stare at everything without being able to make a decision as to what to choose.

on the other hand, when my BGs are high, i get thirsty, hungry, achey and just plain old uncomfortable. not as severe as when i go low, but still i have symptoms that i can recognize.

so here’s the challenge: try estimating your BG level before you do your finger stick or look at your Dexcom. take a guess. how do you feel? what is your body telling you? are you high? are you low? are you feeling within your target range?


I used to think I was pretty body aware but I’m not for this at all. I start to feel bad at 50 and 250 but its hard to tell the difference. I can tell sooner and whether I’m low or high WHILE I’m running, but not when I’m just sitting around. When I’m low, I’m a little shaky and tired. When I"m high it feels harder to breathe, my legs feel heavy (running), and I cramp easily. I’m tired and mentally lazy at both ends.

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Before my CGM several months ago, I was constantly being surprised by how wrong I was, and even now I think I’m near a certain number and then I look at my receiver and BRRRP! Next contestant, please. I’ll think I’m normal, but I’ll be low or high. Am I thirsty because I’m high or because I’ve been too busy to get myself a glass of water recently, or maybe the cheese I had with lunch was too salty? Am I a little foggy because I’m high or because I didn’t sleep that well last night? Usually if I drop fast and therefore have obvious symptoms I don’t doubt I’m low, but if I glide down slowly over many hours I can’t be certain, and I need to check before I treat. Nowadays if I’m off my CGM for a day or so or even a few hours, I test all the time because I just can’t tell.

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dont give up :smile:

I can usually ballpark guess, especially since in the 120s-130s I am STARVING, 140s-150s I’m really thirsty, anything below 70 I’m feeling shaky, but 80-120, I can’t really tell exactly where I’m at, because that’s where I feel good, and actually I feel fine in the 160s-180s, which is usually as high as I go - that leads to unpleasant surprises when I think I’m doing good, and then check and EEK.
I think the hardest part for me is, due to my muscle disorder and breastfeeding, I can feel low (shaky, starving, etc), no matter where my BG is, because I need food (and sometimes just an hour after I’ve eaten!). So that throws me off sometimes.

This is such a great thing to do. I am glad @daisymae started doing this!

It is very useful. In fact, this was one of the things I mentioned to @michel in one of our first PM’s almost a year ago.

One of the important things is to not just feel symptoms and guess, but also connect all the dots. Put together everything you know - your last test number, how much insulin you have had recently, what you have eaten, what you have been doing the past few hours. All those things, connect the dots!

Just try to beat your CGM. Make your prediction, test your BG, look at your CGM. If you were far off, just try to analyze why you missed it.

This is something that really helps you to understand how your body is reacting to everything. It removes a lot of the mystery.


If I’m reasonably active I can guess pretty well at least within ranges…the surprise BG’s are always after I’ve been sitting on my keester for a while.

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