When a person considers using a Continuous Glucose Monitor (CGM), they often ponder their choices. Do they want a Dexcom, a Guardian, a Libre, or another option? In this article, we will compare the Dexcom G7 ® or Libre 3. Which has the best accuracy, and which one is right for you?
Dexcom G7 ®
The Dexcom G7 ® is the most updated version of the Dexcom ® CGM. Its features include:
- approved for use in individuals 2 years old and older.
- uses Bluetooth technology
- sensors last 10 days.
- sensors are water-resistant so it is safe to shower with.
- does not require calibration.
- An all-in-one sensor and transmitter means less diabetes waste.
- 60% smaller than G6
- Has a MARD of 8.2%
- 30-minute warm-up period
Libre 3
The Libre 3 is the most recent version of flash monitoring systems from Abbot. Its features include:
- 14 day sensors.
- Smallest and thinnest sensor for discreet placement.
- Factory calibration.
- One hour warm up time.
- The ability to measure glucose every minute.
- One piece applicator.
- MARD of 7.9%
- Approved in the US and EU for use in individuals aged 4 and up.
Which is more accurate when comparing the Dexcom G7 ® or Libre 3?
There is minimal difference between the Dexcom G7 ® and the Libre 3 but the Libre®3 has been shown to be slightly more accurate. Clinical data for the Dexcom G7 ® shows it has a MARD (the Mean absolute relative difference) of 8.2 percent while the FreeStyle® Libre 3 has a 7.9 percent total MARD score.
Both the Dexcom G7 ® and the Libre 3 ®…
- have the option to use your phone to monitor readings.
- have some form of alert system that can be set. The alarms can become overwhelming for some.
- may have adhesive issues that require you to use other sticking overlays.
- are approved for use without the need for backup readings from a fingerstick meter to confirm accuracy.
- have excellent customer service and replacement policies.
- both are approved for use on your arms.
- both are water resistant
- both currently are working with insulin pump companies to work with devices.
What are the differences between the Libre 3 ® and Dexcom G7 ®?
Differences between the Libre 3 ® and Dexcom G7 ® include
- Dexcom G7 ® has a shorter warm up period.
- FreeStyle LibreLink mobile app for iOS or Android allows data to be shared with up to 20 people which is more than the share app used by Dexcom
- Libre 3 lasts 14 days compared to 10 days for the G7
- In the US, the G7 is approved for wear on the arm and abdomen, and ages 2-6 can also wear Dexcom G7 ® on the upper buttocks, while the Libre 3 is to be worn on the back of your arm
- Libre 3 has a better MARD accuracy percentage.
Which is better, the Dexcom G7 ® or Libre 3?
As with everything, it is up to you to choose the device that best fits your lifestyle.
Both Dexcom and Freestyle have created the smallest sensors than we have previously seen with other generations of continuous glucose monitors.
Neither system requires calibration and neither have transmitters to concern yourself with.
Their price points have become must closer to each other.
A previous deterrent for the Libre 3 was the need to scan your readings, now the Libre 3 will show your readings every minute while the G7 only shows a new reading every 5 minutes.
Users find the accuracy of both systems to be comparable, but one blogger found the Libre 3 to offer the best results in his data-oriented experiment. Ross Wollen of Diabetes Daily also agreed that for him, the Libre 3 was the clear winner.
There are pros and cons to each system. If you are interested in trying a continuous glucose monitor, do your research and choose the sensor that is the best fit for you.
Dexcom, because it is more adaptable and has broader acceptance in the T1 market. If I were T2, I might make a different choice.
My blood sugar fell to 31 overnight and I was going into a diabetic coma when the EMT’s arrived. What do you recommend to provide a loud wake up alarm to avoid this from happening again?
Yikes! That had to have been terrifying! If you are already using a CGM, a couple of things that I would suggest is to put your receiver in a bowl with marbles to help amplify the sound, set add a vibrate feature to your alert to help further disturb you, or consider using the share app if possible. A close friend or family member would also get an alert and could either contact you or the emergency team on your behalf.
Pretty scary considering the alarm on the libre 2 wakes up EVERYONE in the house
Great answer. I’m a Certified Diabetes Educator (CDCES) and recommending the Libre 3 with the Libre Linkup app, so the patient can share her data with her blind husband (her caregiver). Thanks for the well-written article!
Dexcom 7 fails too.frequently. out my first 10 sensors 5 have failed’
Took years to match that with libre or Dexcom 6.
Libre2 – I have found that as T1 it is relatively accurate for my needs as well as readily accepted by my endo and diabetic nurse. It also accepted by both my medical insurers making cost at present $0. Biggest issue has been placement on back of arm an d no where else!
I use my freestyle libra on my leg and reads my blood sugar perfectly.
My life style is extremely active. In the past year I’ve almost started to lose hope. Being in the best shape of my life at 42 but my blood sugar up/down constant. My endo talked to me about Dexcom and after a lot of reading Im hoping it will be a better fit (more accuracy)
(Type 2 diabetics user). I am using the libra system currently and trying (switching) to the Dexcom next. I found a slight discomfort using the libra where a tingling sensation ran down my arm. Also, my last installation of the libra, the sensor stopped transmitting short of the 14 day cycle which was disappointing. I will be interested to compare with Dexcom this coming week.
I highly support any use of a continuous system and was successful in controlling my glucose levels simply by learning which foods most greatly impact my sugar levels. I also valued the alarms with the libra 2 set up and gained more intelligence from these alarms in controlling my type 2 diabetes.
At the Lauren Plunkett link she says she uses the Libre sensor on her stomach AGAINST MANUFACTURER RECOMMENDATIONS.
That makes her conclusion that the Libre is less accurate suspect. I think you should note that in your article, unless you can cite other sources also suggesting that the Libre is less accurate at showing fluctuations?
It’s a very important consideration in selecting a CGM
Thank you for bringing this up. I re-read the Lauren Plunkett article. She states that she had only used the Libre twice on her stomach, so I am not sure if that negates all of her findings. I did add a citation from another professional who suggests that this may be an issue on all CGMs because of the lag.
I have a Freestyle libre 14 day system. I use the libre reader & their app on my phone. The problem is that the two readers don’t communicate or share the data. My phone app doesn’t show me that I just dosed, because that info shows up on the libre reader I keep in my bathroom with my insulin supply s. And vice-versa. Is there a way to make both readers sync information?
From what I understand the short answer is no. The only suggestion that I can find is to just use your phone rather than also using the reader. I would contact FreeStyle to get more specific guidance.
I am a T2 that uses only oral medication and exercise to control my diabetes. I did a lengthy comparison on the Libre2 vs. my SMBG (a One Touch Verio IQ) reader even allowing for the 5 minutes that Abbott says you are behind, and found that the Libre2 was off by as much as 50%! This is unacceptable as far as I am concerned. I wrote a letter to Abbott and told them so and I’ve gone back to finger pricks and my SMBG reader again.
I’m interested in the Dexcom g6 to see if it is more accurate that the Libre2 but I don’t really believe I need a CGM. Still, I read about 15 times a day when I used the Libre2 and about 6 times a day when I use my SMBG reader.
Wash your hands for 30 seconds and thoroughly dry them. That’s for blood circulation. Take 3 verio readings and average them . You can then use that as a calibration for the Dexcom G7.
Yes! I wish that was in the instructions! The fist night of my Dexcom G7 it went off saying I was 45 when I wasn’t…so I called the comoany and they walked me through the calibration. Now every time I change the sensor I calibrate it- and it hasn’t been off even once
Since then. My hope is that it will
Work with the Omnipod Dash as I am T1 for 40yeara and zero complications!!! It can be done!!
My wife and I are very frustrated by the many low false alarms waking us up by my using the Free Libre II.
My meter will show me a reading of 59 and when I do a blood test it will show me a lot higher normal reading. The alarm according to the manual says that it has a range of 20 feet. Several times when we are to sleep the alarm goes off saying “lose of signal “. I keep my meter on my night stand which is never more than 3 fèt away. If I do a blood test using the meter the results can be 20 to 30 points higher than the actual non blood test strip shows. Being a type 2 Diabetic testing many times per day I find this accuracy unacceptable. I have reported this fact to their corporate office and have been told this normal.
I am so frustrated with all the problems that I will probably go back to sticking my finger to get accurate results.
I have reported my problems to Free Libre. And they have replaced my meter and also several faulty sensors. Still having same problems.
Like all Diabetics I love the non stick idea but I believe the idea is ahead of the truly accurate technology!
I’ve been using the Libre 2 for a few months. It’s $75 (with ins) every 14 days. I’ve had to at least a half a dozen sensors replaced. Sure, Abbott offers free replacements if you have the serial number for your sensor.
Minor issues: Sensor comes off easily after a few days.
Major issues:
Sensor stops working before the 14 days (sure, Abbott replaces, but not fast enough).
Sensor usually doesn’t notify (alarm) when BSL is high. Mine is set to alarm when my BSL rises above 180. Twice my BSL has been so high when I scanned the sensor, it just said “HI”. I carry a regular BSL meter. Both times, my BSL was over 450.
When BSL is low, the sensor doesn’t always alert. When I check it, it will often read something like, “Please try again in 10 minutes”. About five minutes later, the Urgent Low alarm goes off.
Wtf. The whole purpose of this is to prevent these highs and lows from occurring in the first place!!
I have been a Type I diabetic for 70, yes 70, years. When I was finally approved fpr the Libre system I was overjoyed. At first the system worked fairly well.. Since, however, the sensors last only a few days. I am totally disappointed insomuch i am now pricking my finger four times daily. Reporting the situation to Libre most times requires three to four weeks before resolutiion.
Type 1 as well! 56 years for me. I have been pretty happy with the Dexcom 6. It is accurate as I compare it to a finger prick just to verify every few days. The best part is that I can put it almost anywhere. Back of arm does not work for me so I put them on my upper abdomen. Waist bands don’t get in the way and I don’t bump into it! It has worked very well in wet environments like showers and the lake. Good luck!
I’m having an awful time with my Libre 2. The first one fell off after I showered. The 2nd one did great now the 3rd one stopped reading accurately after 9 days and now the 4th one had a bent needle but we tried to use it. Bad ideal I was bleeding so bad that blood was running down my arm and my phone would not pick up the sensor. Wondering if the Dexcom is better and the same cost.
Lori, it always seems to depend on the user. People do have issues with sensors not lasting on the Dexcom as well. I have heard more complaints with the Libre, but in saying that, some people have no issues at all. I would contact Dexcom, access their free trial, and see what you think.
I am t2 steroid induced diabetic, i am on libre 2, however this year prior to libre i have been unconscious twice last one four weeks ago when my sugars were 1.1 and i went into unconscoiusness and lucklly the doctors spotted my body fighting for its life to survive and got me back.. so its important that this libre works.
however the last two have stopped working around 7 8 days and abbot replaced, the latest failure has been with it alarming are you ready for this 16 times from 1.24am to 7pm at night saying i am very low or in hypo.. i have no hypoawareness so makes things worse.. so i went back to fingerpricking and it was way out one reading from libre 2 was 3.2 and my normal finger pricking was 7.8.. always refer to normal glucose meters and finger pricking.. by 7pm at night i had enough with the damn thing bleeping constantly and to prove it was faulty i remeoved the libre and an hour later i scanned it on top of the fire and it was telling me i was having a hypo, was not in my body so we knew it was faulty, been onto libre and another replacement but this takes about a week to come.. if these are failing at 7 days much more i want to switch to dex com to trial.. i need an accurate sensor esp as my sugar drops really quickly and then unconscious, its bad enough without that never mind faulty alarms and sensors
All I can add, is that Abbott customer service sucks. On the week end they. Don’t answer the phone. My body doesn’t know the difference in Saturday or Tuesday.
I was on the Dexcom 7 last year and due to an insurance change i had to switch to the Libre 3. I find it frustrating that the Libre 3 does not allow fingerststick calibration. It is very inaccurate reading me in the low 60’s when I am around 115. The alarm for urgent low goes off all night when my sugars are normal, I’m a bit sleep deprived to where I feel like I am going to chuck this Libre 3 in the trash. I am trying to give it a shot, though. But yeah Dexcom 7 is far better.