So after seeing loads and loads and LOADS of debates about which is better the Libre 2 or the Dexcom G7. I’ve decided to conduct my own research in find out which CGM (Continuous Glucose Monitor) is better. I am not paid by either companies, so the feelings and findings in this research are non bias. I will run in for 7 days total. Which is best? read my findings below.
Set-Up & Insertion:
with both sensors make sure you clean the area of application first with an alcohol wipe.
Libre 2: With the Libre 2 you have 2 components, 1 is firing mechanism (so to speak) and the second is where the sensor is. You check the codes to make sure they match, you then have to line up 2 lines and click them together, which connects the sensor to the firing mechanism. Once this is done you press down the sensor onto the skin, its makes a click sound and then you wait for 10seconds (well I do) to make sure its firmly in place. Totally painless and easy to do.
Dexcom G7: With the Dexcom g7 you have one component to which you screw the cap, press against where you want it put (was arm for me) and press the button on the side, and it shoots it into your skin. Then you rotate your finger around the tape of the sensor making sure its firmly in place. Dexcom even supply a skin patch to go around the sensor to ensure its secure. Totally painless and very easy to do.
Winner of the category: Dexcom – The box is smaller, its just one thing to mess around with (not two yogurt pots – yes I call then yogurt pots lol) and its has an actually clicker to shoot it in.
App Connection:
Libre 2: You have to scan your phone against the sensor, to which will start the warm up time which is 60minutes (1 hour).
Dexcom G7: You have to scan a QR code or manually input a 4 digit code into the app to start the connectivity and warm up process which is only 30 minutes.
Winner of the category: Dexcom – This is simply due to the fact that it has a 30 minutes warm up time leaving you less time without a CGM.
The App & Alarms:
Libre 2: The graph is more graph looking, its colourful and looks more attractive. Having the goal of staying in the green is a nice feeling! Alarms will go off, and although its a CGM you have to manually pick up your phone and scan to acknowledge it, meaning your more likely to react to an alarm.
Dexcom G7: I cannot take screenshots, its annoying me so much! I dislike the little dots all over the place, I dont like the fact time in range is grey. Its just boring. On the other hand though, the alarms are AMAZING!! It will give you a warning like you will be 3.1mmol in 20minutes if you do not act now. This is a nice warning and feature. The default alarm sounds aren’t too bad either. You do not need to scan to disable the alarm you can literally just dismiss it, which can be scary if having a hypo at night (because we all know how we auto pilot an alarm clock).
Winner of the category: Libre – Much nicer app, allows screenshots so can share on social media, alarms are better as have to scan. Although I did love the warning trend of the dexcom.
Day 1 (26th August, 2023)
So far the readings are matching up well with each other. The Dexcom is a bit more responsive once eaten (by about 10minutes), as for comparison the Dexcom reads: 5.8 and the Libre reads: 5.9 and my finger prick reads: 6.3 – This actually means the Libre is reading closer to my actual glucose than my Dexcom is. Although I have just put on my Dexcom, so might need some getting to know me lol. My Libre has been on my body for 16 hours so far. So people who say Libre reads bad within the first 24 hours please let that myth leave your brain now.
First low alarm. My Libre alarms are set at 4.7 and I got notified about it and scanned my arm. A little while later I actually forgot I was wearing a Dexcom too, and I had an alarm which I could dismiss with a click and then it told me, if 20 minutes I will be 3.1mmol if I do not react now.
After lunch I had a slight spike, and on my finger prick it was 13.8, yet on Dexcom is was 8.0 with a steady arrow and on Libre it was 11.1 with a diagonal up arrow. I’ve corrected and 15 minutes later both sensors displayed 10.5.
Day 2 (27th August, 2023)
Last night, I went out to have a few beers (literally just 2) because I knew it would be a good test on the sensors… and this morning , I woke up and finger prick reads: 13.6, libre reads: 13.1 and dexcom reads: 10.1, so judging on how the sensors are reading libre can handle alcohol much better.
Both sensors generally run accurately. the only time they differ is when I eat. The libre seems to be more reactive and accurate compared to finger prick when eating, which has shocked me.
Both sensors survived a shower, YAY!
Day 3 (28th August, 2023)
Hypo during the night on both sensors, both accurate.
2nd shower and both sensors still on and no signs of losing their stickiness, which is great!
Gone to Clacton pier today, and both sensors running perfectly.
Day 4 (29th August, 2023)
Woke up in the morning due to high sugars (I was drinking sex on the beach cocktails). Finger prick: 14.3, libre 2: 16.3 and dexcom 15.8… so all are reletivly close. After correction the libre was slower to respond to the lowering on my sugars. The dexcom was triumph here.
Swam in the sea in the morning, both sensors still functioning, even with the water being so cold. Readings are 8.9 finger prick, 9.1 on libre 2 and 8.3 on dexcom, libre is still closer for me. My trust is swaying way more towards the libre 2 rather than the dexcom at the moment.
Day 5 (30th August, 2023)
Decided to remove the dexcom early as my battery was getting drained way too much.
My verdict is for Libre 2. Dexcom is still a great CGM though. I am actually so surprised as I thought the dexcom g7 would be soooo much better than the libre 2, but I was wrong. I will no longer keep slating freestyle libre 2 as the sensor is amazing. It just struggles a little around food.