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 G6® or Libre2. Which has a great accuracy and which one is right for you?
Dexcom G6®
The Dexcom G6® is the most updated version of the Dexcom® CGM. Its features include:
- approved for use in children 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. Users can still choose to enter a calibration if they would like to or feel that the sensor seems inaccurate.
- has a 2-hour warm-up period.
Libre 2
The Libre2 is the most recent version of flash monitoring systems from Abbot. Its features include:
- 14 day sensors
- Small sized sensor for discreet placement
- Factory calibration
- One hour warm up time
- The ability to measure glucose every minute
- A new designation as an integrated Continuous Glucose Monitoring System (iCGM)
Which is more accurate when comparing the Dexcom G6® or Libre2?
According to an article from the DiabetesMine, there is little difference in accuracy between the Dexcom G6® and Libre2.
Clinical data for the Dexcom G6® shows it has a MARD (the Mean absolute relative difference) of 9 percent while the FreeStyle® Libre 2 has a 9.3 percent total MARD score (9.2 percent for adults, and 9.7 percent for children). In other words, the Dexcom G6 is slightly more accurate, especially in children.
What are their similarities?
Both the Dexcom G6® and the Libre 2…
- 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.
What the difference between the Libre2 and Dexcom G6®?
Differences between the Libre2 and Dexcom G6® include
- The Libre2 currently is not being used to communicate with any insulin pumps on the market.
- The Dexcom G6® has a transmitter that sends continuous data to the receiver (phone). The transmitter has a 3-month battery life.
- The Libre2 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
- According to Lauren Plunkett at LP Nutrition Consulting, the Libre2 doesn’t track blood sugar fluctuations fast enough and can be unreliable when dealing with rebounding lows and corrected highs. (New York DCES Stahl feels that CGM users often find this in situations like as postprandial (post-meal) or during exercise in which glucose is changing rapidly.)
- The Dexcom G6® can be placed on your arms, stomach, and legs without impacting accuracy.
Which is better the Dexcom G6® or Libre2?
Users seem to be torn on which system is the best. There are many reasons to like the Dexcom G6® and many reasons to like the Libre2. Two things seemed to stick out, however.
If you are concerned about cost, the Libre2 seems to be the clear winner. It has a lower price point, and many users find it to be reliable enough for their needs.
If you want accuracy and more detailed alerts, then Dexcom G6® would be more beneficial for you.
Lauren Plunkett at LP Nutrition Consulting summed it up the best. If you are active and may have sudden changes in blood sugar, the Dexcom G6® may be your best option. If you are looking for a basic system that shows blood sugar deviations the Libre2 offers affordable and efficient monitoring.
As with all diabetes products, educate yourself. There are a variety of continuous glucose monitors on the market besides these two. Know the features that you require in your device and discuss your options with your diabetes team. Not everyone is the same and therefore not every diabetes device will be right for every person with diabetes.
Compare CGM Features
Download the free PDF to compare Continuous Glucose Monitors
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
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.
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.
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.