Weight Loss and Dexcom correlation?

Hi all,
I’ve recently started using the Dexcom G6 and Omnipod system. Over all it has definitely helped me manage my diabetes a lot better than before, but I am still figuring out how both systems work. Ever since getting on the Omnipod, I have had to adjust my diet completely and with doing so, have lost a little weight. As of recently, I’ve noticed that some of my Dexcom sensors and transmitter have failed me, where I was more than 50 points off, no matter how many times I’ve recalibrated. Now my question is, what am I doing wrong? Does losing weight play a factor with it being off? Or is it a manufacturing issue? The last time my sensor failed, Dexcom was hesitant to reimburse me for the 2 sensors I wasted, but with enough persistence, they sent me 2 new ones. With everything in life, new thing take some time to adjust to but this new system has caused alot of frustration and stress for me. My next question is for the people who already have the Dexcom G7, what are the reviews? How are people liking it? Are there fewer reading errors?

I really appreciate the time you all take to read my lengthy message!

I’ve been using G7 for 5 months with MDI. I have no knowledge of G6 as I went from Freestyle 3 straight to G7. The most I’ve ever had to calibrate a G7 sensor was two times, as a new sensor readings were all over the place, but that sensor settled down and worked great afterward. Have never noticed issues with weight gain or loss. My weight only fluctuates between +/- 3lbs so possibly not enough to trigger a change.

Comparing G7 to Freestyle 3… I noticed a big difference in reading accuracy. G7 was far more accurate below 90 and above 150’ish. Both were highly accurate between those ranges.

Note that I have found that arm placement of the G7 between bicep and tricep limits new sensor weirdness. Wondering if anyone else notices this?

@Karii0907 Welcome Karina to the JDRF TypeOneNation Community Forum!

A couple of comments, First: I have been using the G6 for about four years and find they work quite well for me, accurate and VERY rarely have I calibrated. I did meet a woman this week who has lived with diabetes for a few years for whom the G6 doesn’t work at all and needs to use the Libre with her OmniPod5. Like many devices, it can’t be expected that G6 can be right for all. The issue you are experiencing might be caused by over-calibrating; in effect, with each calibration you make, the sensor will spend 12 to 24 hours adjusting itself to your body - read the “When to Calibrate” in the Dexcom Q&A and follow the advice in the table.

Second, why did you change your diet to fit the OmniPod? In my way of looking at diabetes and these “assist gadgets” changing diet to fit a device is doing stuff backwards. The goal I’ve followed during seven decades with diabetes is to use insulin to allow me to live a full, active and productive life. To live a healthy live and make diabetes fit - nerver to let diabetes rule my life.

Hi @Karii0907 . It sounds like a bit more training may be in order. I’ve been pumping for close to 30 years now❗and when I switched to Omnipod5, even after watching the training videos and reading War and Peace - I mean the manual (Yes,I read The. Whole. Thing) - I still had a lot of questions and needed a good deal of clarification from my trainer. It functions differently from other pumps but even if you’ve never used one before you do need a more thorough of its workings than with Tandem or Medtronic products. So do contact your trainers - Dexcom as well - so you can get a better understanding of how they work - separately and together.
When I find myself gaining weight quickly it’s because my basal insulin insulin (with Tandem or Medtronic) is too high and I have to cover lows: that was a key that I needed to adjust my rate/s. If you are having to change your eating to accommodate your pump then there is something going on with your settings. I’ve recently found myself gaining weight on my Omnipod for that very reason: since auto mode does not use basal rates I got in touch with my trainer (my physician got trained on Omnipod5 after I did) to see what I should adjust. I won’t tell you what settings I changed since you need to get some more time with your own trainer, but suffice it to say it solved the problem. In my case I was gaining weight and you have been losing but adjusting your settings should help you eat as you want, not as your pump demands.
You also need to address the Tandem issue: @Dennis may have hit the nail on the head when he referred to over-calibrating (by the way, since you’re new to the forum let me just say that Dennis has a huge, impressive wealth of knowledge and wisdom to share).
Dexcom does tend to give false lows the first 24 hours but it should not be necessary to calibrate frequently. Hydration and other factors can affect CGM accuracy - below is a link to an article you might find helpful.

You might find that certain insertion sites work better than others, so keep a log or use a diagram to see if that’s the case. I’ve heard that people who are very lean have problems with the sensors - not enough fatty tissue to get a reading, so maybe try “fleshier” areas.

Acetaminophen pain relievers which were not supposed to be used with Dexcom’s G4 and G5 we approved for the G6 - but they might still cause issues:. Interfering Substances and Risks | Dexcom

Please keep us posted on how you’re doing, and I look forward to reading your contributions!

PS - I started on Omnipod5 about a year ago and just recently checked out this Juicebox podcast. I find it very helpful and wished I had watched it since. But please work with your trainer.

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Hello Karina and welcome to the forum. Good to hear you’ve got a combo that is working better for you. Are you enjoying your new diet?

Generally weight loss doesn’t affect the G6 (and the G7). Now if we are talking about burning a lot of fat the skin doesn’t exactly spring right back over our insides. Ever watch a Biggest Looser finale? The Dexcom would have a hard time with that much weight loss because the interstitial fluid the G6 is measuring the sugar in isn’t the same all over a body like that.

After a few years with the G6 I’ve found a few spots on my abdomen where the G6 is fine but if I go an inch closer to the side the numbers are bonkers. When I wear the G6 on my arm I am more likely to nick something that bleeds throwing off the numbers. These are just personal examples, your cases of wacky numbers will due to something probably completely different.

One note on Dexcom accuracy is that the numbers are only supposed to be close enough to make treatment decisions. So a 50mg/dL difference for a couple or even 20 readings is unusual but it doesn’t necessarily mean the sensor is bad. Dexcom tries to do better but doesn’t always succeed.

The G7 is the same sensor wire attached to a new package and the clinical trial they submitted to the FDA says its better than the G6 but that “better” is within the error bars. I expect for everyone who the perpendicular wire or new package works better for will be someone else who it works worse for.

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Chris reminds me of an important point: Dexcom is considered accurate if the difference between it and a fingerstick is up to 20%: so if it shows 200 but your fingerstick is between 150 and 250 it’s acceptable, even though logically we hope the numbers will be much closer numerically. Here’s a chart to show you acceptable ranges in case you don’t feel like doing the math.

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These have all been great replies. I’ve recently been talking my elderly uncle through some troubleshooting with his dexcom vs finger stick numbers. He was very proud to share he calibrated the sensor so many times, and got it to 2 pts of finger stick. Although we do count on the sensor for treatment decisions, it is not 100%, but a tool.
One question I have in your situations…what were the arrows doing when the numbers were different? With the lag time of 10-15 min between blood and interstitial fluid, there can be a fairly large discrepancy between numbers when arrows are :arrow_down::arrow_down: or :arrow_up::arrow_up:. Its been 100 pts or more for me, and its not inaccurate…just not keeping up with the rapid changes.

Karen @T1Dx2, it is OK to do a fingerstick at any time just to see, but I [and Dexcom] strongly advise against calibrating when there is any arrow other than a horizontal.

Keep in mind, that “double arrows” indicate that BGL is changing, or anticipated to change, at greater than 3 mg/dl / per minute. Over a 15 minute period, this means BGL will be more than 45 mg different - possibly 125 mg different.

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Yes. I guess I didnt say it correctly…but I very rarely calibrate. Its ok for them to be different…and 20% difference is within there variance.

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