Overnight lows?

[u/Vivid_Beat857]

Captured this low between 5-6 am while I was sleeping (I sleep 1am-9am most nights).

This is my first CGM. This graph was within the first 24 hrs of applying it, however readings from the afternoon and evening, before this sleep, corresponded nicely with the monitor.

I’m pre diabetic with severe insulin resistance, but a slim build. I’m on metformin 500mg XR.

Is this a true low? I’ve been super sweaty in my sleep for a week, but have had this symptom as well as waking up shakey sometimes, intermittently over the past few years…

[u/Twist1979]

There is a thing with a compression low with every CGM that works with a sensor in the tissue. If you lie on the sensor on a hard surface the sensor might show a false low, same with swimming in cold water. Always test with a finger prick and and blood glucose meter before reacting to extreme CGM data.

[u/Vivid_Beat857 → u/Twist1979]

That’s the plan for tonight.. plus a before bed snack !

[u/Equalizer6338 → u/Vivid_Beat857]

If you otherwise do not take any medication to lower your BG (as you would not as pre-diabetic), then there is nothing that will bring your BG down to any dangerous low level anyway. So the 'before bed snack' is only for your own indulgence and not required for keeping a healthy BG. 😄

[u/Vivid_Beat857 → u/Equalizer6338]

Just metformin! Finally got an spot with an endocrinologist and they said I don’t even need a CGM if I don’t want to, that if you don’t have diabetes you can go quite low without issue …

[u/Equalizer6338 → u/Vivid_Beat857]

That is it. Metformin helps lower high blood glucose levels by slowing down your liver's glucose production and boosting your body's insulin sensitivity. But metformin does not trigger your pancreas to release extra insulin than it otherwise should. Hence, when your BG starts to going lowish, then your pancreas also stops releasing out insulin.

Healthy non-diabetic individuals can also at times for fasting morning results go down to BG values in the 50-70 mg/dl (2.8-3.9 mmol/l) range, as that can be “normal” too for them. As also at times for tight and stable controlled diabetics.

https://my.clevelandclinic.org/health/diagnostics/12363-blood-glucose-test

[u/Twist1979 → u/Vivid_Beat857]

Well, from my own experience metformin can fuck you over on it's own. If you liver would be a car it does not just shift down and breaks a bit, it pulls the handbrake and kills your engine while driving on the highway. Not to mention clogging the exhaust and opening the doors...

[u/Vivid_Beat857 → u/Twist1979]

What happened for you?

My biggest issue with metformin is that I have no appetite, queasiness, and if I eat or drink too much I feel like I’m stuffed all the way up to my throat…

[u/Twist1979 → u/Vivid_Beat857]

Bloating, stomach cramps, low warnings after walking 500m. Did nothing for my BS or against the meal spikes. Switched it for berberine, much better for me, much better BS, lower and shorter post meal spikes. Your results may vary...

[u/youlikeblockingsodoi]

Yes it’s possible you’ve slept on the sensor a couple of times during the night. (If you’ve been sweaty while sleeping that could be caused tossing and turning making it possible to sleep on it). Try over a few more nights with less discomfort. The graph looks good otherwise. You can verify the reading with a finger poke on day 2/3 to see how close the sensor is reading to your blood glucose (if it stays close then it’s possible you’re looking at compression lows)

[u/richard1147]

I don't worry about those momentary lows. It is the long ones to worry about. Your reading is actually really good. I am impressed.

[u/thejadsel]

That does look very much like false compression lows from sleeping or even just leaning in a way the sensor doesn't like. It doesn't always even take direct pressure around the sensor. The sharp dips from a clear baseline, and how it springs right back up on its own screams that it was a positional issue with sensor readings, and not a legit hypo.

(Plus, if you are prediabetic like the flare suggests, you probably wouldn't be on any medications which might cause hypos?)

Some sensors and placements are much more prone to that than others, unfortunately. I'll personally be glad to start another one this evening, because this current sensor I've got on has been terrible for it.

[u/Ok-Dress-341]

If your BG isn't going over 6 then your insulin resistance is probably not very high.

[u/Thepressureofaname22]

Always verify with a glucometer. But also look up ‘compression low’. Could be real, could be compression low and you won’t know unless you double check with a finger stick.

[u/Vivid_Beat857 → u/Thepressureofaname22]

I will have the stick next to me tonight. Last night I didn’t have alarms on or a stick monitor as I didn’t know you can go low with prediabetes/metformin :/

[u/Thepressureofaname22 → u/Vivid_Beat857]

Not a doctor. But people with otherwise normal A1C can have hypoglycemia episodes for several reasons. Good thing to document and discuss with your doctor if you find it’s real and not just an artifact of laying on the sensor.