For the previous ten days, I used to be fortunate sufficient to strive the Dexcom G7, the long-awaited, hotly-anticipated, model new steady glucose monitor (CGM) from Dexcom.
The enterprise’ earlier mannequin, the G6, was the “killer app” of CGMs, a tool so user-friendly that it even satisfied many individuals with out diabetes that they needed the tech, with such beautiful blood sugar accuracy that the FDA allowed Dexcom to inform customers that they didn’t want fingersticks anymore. Dexcom didn’t relaxation on its laurels — the G7 is totally redesigned, and is a big enchancment over the outdated mannequin.
But Dexcom’s greatest competitor, Abbott Laboratories, was busy too. In October 2022, I had the possibility to put on a FreeStyle Libre 3, and I known as it the perfect CGM I’d ever tried. How does the Dexcom G7 get up?
To discover out, I wore each CGMS — one on every arm — for ten days. Dexcom kindly offered me with one sensor to strive as a journalist. Abbott has beforehand carried out the identical, although this time I used a Libre 3 sensor that I purchased with my very own cash (I’m a daily consumer). In every case, my opinions are completely my very own.
Here’s the way it went:
Size
If you’re used to the older technology of CGMs, you’ll discover that each the Libre 3 and the G7 are impressively small. The G6 was fairly modern, however I approach at all times conscious that it was there, caught onto my physique, and had a behavior of bumping it into door frames the and like.
The new G7 is tiny! Dexcom reviews that the brand new system is 60 % smaller than the G6. Even if nothing else in regards to the expertise have been improved in any approach, that slim profile could be properly price trying ahead to.
But the Libre 3 is even smaller than the G7 — it’s in regards to the measurement of two pennies stacked on prime of one another.
The fact is that they’re each sufficiently small that I don’t discover them in any respect throughout my day. They are as mild as heck and about as obtrusive as a Band-Aid.
The creator and his two CGMs.
The Libre 3 wins right here, nevertheless it doesn’t actually matter — each CGMs are so small that you’ll in all probability neglect you’re sporting them.
The Transmitters
Surprise — there are not any transmitters right here.
One of the foremost benefits of the Libre system was once the shortage of a transmitter. The Libre sensor, the little spherical system that you just stick into your pores and skin, was all-in-one. The Libre 3 preserves this straightforward design.
By distinction, the Dexcom G6 required you to snap a transmitter out of your outdated sensor and into your new one. Although there have been some benefits to this method — Dexcom customers may hack their G6 transmitter with a purpose to get further days out of their costly sensors — the method was cumbersome. You needed to take care of two components, every with a really completely different working life, and it elevated the technical issue of the Bluetooth pairing ritual you wanted to carry out to get every new sensor working.
The G7 is, just like the Libre 3, an all-in-one sensor. It is totally disposable. Though the G7 will not be hackable, it’s now far simpler to change from an outdated sensor to a brand new one.
Scanning
If there was one apparent sticking level with the earlier Freestyle Libre CGM techniques, it’s the truth that customers didn’t simply get their blood sugar numbers mechanically beamed to a devoted receiver or smartphone. They needed to manually scan the sensor by holding their system over the sensor for just a few moments. In our survey of CGM customers, handbook scanning was continuously talked about as a significant annoyance with the older generations of Libre CGMs.
This scanning motion is totally pointless with the Freestyle Libre 3 — because it was with the G6 and continues to be with the G7.
With both system, your smartphone updates with new blood sugar readings mechanically.
There is one important distinction between the 2: the Libre 3 will present new blood glucose readings each minute, whereas the G7 solely updates each 5 minutes.
Sensor Life
This is a transparent win for the FreeStyle Libre 3.
The Freestyle Libre 3 is rated for 14 days.
The Dexcom G7 is barely rated for 10 days (10.5 days, actually, when you think about the 12-hour “grace period” for switching over to a brand new sensor).
Libre’s longer life is a big benefit — not solely does it imply fewer annoying changeovers, nevertheless it additionally reduces the period of time you spend sporting model new sensors, that are much less correct.
Dexcom has advised Diabetes Daily that it’s working exhausting on extending the sensor life to 14 days. But, for no matter cause, they haven’t been in a position get there but.
Application & Start-Up
For each fashions, sensor software was painless and practically easy for me. Each comes with an easy-to-use one-piece applicator. Each is pressed flat in opposition to the pores and skin. For older CGM fashions, it was typically a good suggestion to look at a YouTube video to see precisely the best way to insert the sensor. But the Libre 3 and G7 are each easy and intuitive.
It was simple to pair every CGM with my smartphone. For every, I downloaded the official app, and adopted directions on the app. With the Libre 3’s, you merely faucet your telephone in opposition to the sensor in your physique. The G7 was barely extra complicated — you enter (or take a photograph of) a code on the field.
The Libre 3 offers you your first glucose measurement in a single hour.
The G7 is quicker: It’s up and operating in solely half-hour.
The Adhesive
I used to be stunned to see that Dexcom consists of and requires you to use a supplemental adhesive. This step was actually easy, however I needed to stroll over to a mirror and fumble with a donut-shaped sticker to get it correctly connected to each the G7 sensor and the encircling pores and skin. It’s a minor annoyance, and the additional sticker makes the G7 extra conspicuous.
The adhesives for each techniques carried out completely for me, staying firmly caught onto my pores and skin for the complete 10- or 14-day put on size. I didn’t actually check it although — it’s not summer season, and I wasn’t swimming or sweating.
Adhesive high quality is an element for which your mileage might actually range. Many individuals with diabetes wrestle with CGM and insulin pump adhesives — there’s a whole Facebook group, with over 15,000 members, devoted to troubleshooting rashes and adhesive allergies from CGMs. The producers have been at pains to scale back the incidence of those annoying and sometimes deal-breaking pores and skin points. But it’s potential that one system is less complicated in your pores and skin than one other, and that might be sufficient to make the distinction for you.
Other Features
Each system brings an analogous suite of additional options, together with:
- Glucose alarms
- Glucose development arrows
- Remote monitoring for members of the family/caregivers
- Data sharing with healthcare professionals
- Data evaluation within the smartphone app
Though I didn’t use all of those options, I didn’t discover a massive distinction between the 2 techniques. Each app is engaging and intuitive.
Accuracy
Both CGMs are completely ok to make use of for diabetes administration.
Throughout the 10-days I examined my two CGMs in opposition to one another and in opposition to my glucose meter. All three have been constantly in the identical ballpark. I felt utterly assured utilizing my blood sugar measurements to information my consuming and insulin dosing selections. I had no want for fingersticks.
Did one system carry out higher than the opposite? Not actually. It is feasible that the G7 — even supposing it solely updates each 5 minutes, moderately than each one minute — was faster to establish blood sugar tendencies. It appeared to award upward and downward arrows earlier than the Libre 3 would throughout time once I new, from meals or train, that my blood sugar was about to vary quickly. But it’s unimaginable for me to say if this can be a actual benefit for the G7 or only a fluke throughout a single small experiment.
As I write this line, my Libre 3 believes that I’ve a blood sugar stage of 95 mg/dL. The G7 says 98 mg/dL. Such tight settlement was very typical, and neither was constantly decrease than the opposite. After 10 days, every app reviews precisely the identical common blood sugar stage: 105 mg/dL.
The G7 could be calibrated utilizing a studying from a blood sugar meter. The Libre 3 can’t be calibrated. I by no means felt the necessity to calibrate, both approach.
Both Abbott and Dexcom declare to have created the world’s most correct CGM. As far as I’m involved, they’re each a lot correct.
There have been two exceptions to their common consistency:
- CGM sensors are recognized to be much less correct in the course of the first 24-48 hours.
In truth, many individuals with diabetes have realized to extra or much less ignore their CGMs throughout that first day or two.
To be completely trustworthy, my G7 was a nightmare in the course of the first day of use. It repeatedly bombarded me with very loud misguided low blood sugar alarms. I turned off as many non-obligatory alarms as potential, however ultimately I needed to bury my telephone below a pile of pillows and blankets.
The Libre 3, alternatively, gave me good measurements immediately. But I’ve used it lengthy sufficient to know that the Libre 3 will not be good each time. In truth, the very first time I used it, it had the identical downside because the G7, sounding false low alarms in the course of the evening. I’ve no cause to suspect that both the G7 or the Libre 3 performs higher than the opposite in the course of the first day or two.
And after that first day, neither system gave me a single false alarm.
- CGM sensors are slower than old-school glucose meters.
A CGM sensor doesn’t truly pattern your blood — it samples the interstitial fluid that surrounds the physique’s cells. Interstitial fluid carries vitamins from the blood capillaries, together with glucose, which makes it a reasonably dependable indication of blood sugar ranges.
It takes a short time for the glucose in your blood capillaries to filter into the interstitial fluid. When your CGM offers you a brand new glucose measurement, it’s actually displaying you what your blood glucose stage was about 10 minutes in the past.
This 10-minute hole was plain to see as I examined my blood sugar repeatedly after a having fun with a very difficult meal. My old-school meter registered the glucose spike quicker than both CGM did. But this doesn’t matter a lot — I might moderately have a CGM give me steady sluggish measurements than have to make use of fingersticks time and again after I ate.
Operating Range
This was the shock issue that actually made a distinction to me.
The Libre 3 has a Bluetooth vary of 33 ft, in comparison with the G7’s 20 ft. This made an enormous distinction for me. I don’t have a big home, however once I left my telephone in a single room and went to a different, I continuously discovered that the Dexcom app misplaced contact with its sensor, whereas the Libre 3 stored churning out glucose readings. Given that it could typically take the Dexcom a number of minutes to get again on-line, the Libre 3 ended up being considerably extra dependable.
Cost
Given the vagaries and complexities of healthcare economics, it’s unimaginable to say which CGM system would value you extra.
For these of us fortunate sufficient to have beneficiant medical health insurance insurance policies (or stay in international locations with sturdy socialized healthcare techniques), these important gadgets might be virtually free. For a few of us, they might be out of attain.
As of this writing, a month of Dexcom G7 sensors prices $378 at Amazon’s on-line pharmacy, with an “estimated” value of $60 after insurance coverage.
In distinction, an analogous provide of FreeStyle Libre 3 sensors prices a mere $132 — however the estimated value after insurance coverage is $75.
But we will say that the Freestyle Libre merchandise normally value lower than the competing Dexcom merchandise. That’s been true for years, although the specifics of your insurance coverage state of affairs will finally decide your value.
Interoperability
Neither of the brand new CGM techniques is prepared to be used with an insulin pump in an automatic insulin dosing (“closed-loop”) system.
That will change.
Dexcom and Abbott are at present racing to get closed-loop integration going as shortly as potential.
Dexcom appears as if it might have a head begin — its G6 can already combine with the insulin pump and dosing algorithms from Tandem and Omnipod. But Abbott, which has been slower to safe comparable relationships, lately announced that it had obtained FDA clearance to be used with automated insulin supply.
If closed-loop pumping is your precedence, you’ll have to attend and see.
The Verdict
All issues thought-about, I most popular the FreeStyle Libre 3. It’s barely smaller, it lasts longer, and I actually appreciated the bigger working vary. It is feasible that the Dexcom G7 is a bit bit higher at responding to blood sugar adjustments, however the distinction (if it’s actual) is refined.
But actually, these are each excellent merchandise, and every is lightyears forward of the expertise that was obtainable just one 12 months in the past. You’ll be proud of both one. Go with whichever mannequin your insurance coverage prefers.
