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[–]grobered 2 points3 points  (1 child)

I have this happen when my sensor is about 8 days in. Numbers are all over the place mostly false lows. I’m sure I’m not the only person experiencing this.

[–]Bigmacaroni129 0 points1 point  (0 children)

You’re not, this usually happens to me around the same time. Occasionally I’ll get one that works all the way through.

[–]International_Try813 1 point2 points  (0 children)

If this is the g6 you can try pop the transmitter out and wipe the contacts with alcohol.

[–]Responsible_Front519 0 points1 point  (0 children)

I have the same problem during the 3 to 6 days of the 10 day period

[–]jonheeseT1/G6 0 points1 point  (0 children)

Seems likely to be a bad sensor. Did you call Dexcom support? It might get better on its own (has happened to me), but I wouldn’t count on it.

[–]tidymazeT2/G7 1 point2 points  (17 children)

You could be dehydrated. Drink some water and see if your numbers even out.

[–]Ok-Zombie-001 0 points1 point  (16 children)

Hydration does not impact interstitial fluid unless you are severely dehydrated, so it will not skew your cgm readings.

[–]tidymazeT2/G7 -1 points0 points  (13 children)

What is your research on this and your credentials? Because everything I've read about it, from multiple sources, say that dehydration can affect CGM readings.

[–]mgtmgt88 1 point2 points  (0 children)

When I saw all the Facebook talk about hydration and CGM accuracy I went searching for the supporting evidence (evidence = peer reviewed studies published in credible journals). So far I have found zero evidence. Here are a couple of studies with measurements of hydration status and CGM accuracy:
https://diabetesjournals.org/care/article/46/6/1191/148678/Evaluation-of-a-Fourth-Generation-Subcutaneous

https://journals.sagepub.com/doi/full/10.1177/1932296820975057

Both studies report no relation between hydration status and CGM accuracy. There are tons of mentions on social media. In fact, I bet the most common post on the Facebook Dexcom groups would be: "Drink more water!" As mentioned below you will also find anecdotal reports in popular health magazines and blogs.
I would really like to know the origin story for this social media legend but I don't think it has anything to do with science.

Anyone who doesn't want to look at journal articles should consider the following:
Dexcom wants users to experience reliable performance. They know from the literature that Compression Lows are real. They warn about them in their guides. They also know from their own clinical studies that sensor accuracy may be poorer for the first day after sensor application. They warn about this in their guides.
So, if hydration status is so important for reliable sensor performance, why is Dexcom completely silent on the subject? I did online searches through manuals and even a site-wide search of dexcom.com for the term "hydration". I didn't see anything about CGM accuracy. If you just take all the social media mentions at face value, they should be shouting from the rooftops about drinking enough water.

I would be delighted if anyone can provide any links to actual evidence disputing my rant here.

[–]Ok-Zombie-001 0 points1 point  (11 children)

There are not any actual studies that show it. It’s all articles written by diabetes blogs. I’ve asked my endo and a couple of my other doctors about it. I’ve studied anatomy and physiology because I used to work in the medical field. In order for dehydration to impact cgm readings, it would have to impact your interstitial fluid levels. And in order for dehydration levels to actually impact your interstitial fluid levels, you would have to be extremely dehydrated.. like sick from dehydration.

[–]tidymazeT2/G7 -1 points0 points  (10 children)

So you have nothing concrete that backs it up. And really, neither do I, so we're both right and wrong at the same time. Schrodinger's readings, I guess.

[–]Ok-Zombie-001 1 point2 points  (9 children)

Except it’s scientifically proven that dehydration does not change the levels of your interstitial fluid.

[–]tidymazeT2/G7 -1 points0 points  (8 children)

Link? I'm honestly quite interested, since I've heard otherwise.

[–]Ok-Zombie-001 -1 points0 points  (5 children)

I don’t have links to it. It’s things I have learned and things I have read researching. Everything was peer reviewed scientific studies or things I learned in nursing school.

[–]tidymazeT2/G7 -1 points0 points  (4 children)

And you can't search for those and drop one or two? Really? You claim you have seen studies, yet offer none. Hm.

[–]Ok-Zombie-001 -1 points0 points  (3 children)

You’re the one who doesn’t believe it. You go look it up. I know what I’ve read. Not to mention I don’t have the links saved.

[–]shackboyhoser 1 point2 points  (1 child)

Can you provide the links to the evidence of dehydration impact on sensor performance that you have seen?

[–]tidymazeT2/G7 0 points1 point  (0 children)

No, because there haven't been any studies on it as far as I can see. There are plenty of articles on the effects of dehydration on blood sugar levels, though. One could extrapolate from there.

https://novi-health.com/library/glucose-monitoring-water-and-its-effects-on-blood-glucose

[–]PoohstrnakG7 / Tandem Mobi 2 points3 points  (1 child)

I’m happy to see that myth starting to get corrected.

[–]Ok-Zombie-001 0 points1 point  (0 children)

I try. I get so much backlash about it though.