I just got today my freestyle libre and i was feeling week so i checked myself with the freestyle libre and it showed 65 so i had some sugar… then it kept showing in the low 70 about 1 hour after i took the sugar i checked with the freestyle libre and my regular glucose meter and my results were
freestyle libre-70
glucose meter-100
pretty interesting does anyone know a answer for this
thanks aton
I don’t use the Libre so my answer is based on my CGM (Dexcom) experience. To start with, the Libre measures changes in the interstitial fluid below your skin that track actual blood glucose changes. The interstitial fluid changes generally occur about 15 minutes after the blood glucose changes.
The second thing that may be going on is the fact that this is your first day with this sensor. It’s well known, at least amongst CGM users, that the first 24 hours can include erroneous readings, sometimes rather significant.
Lastly, our glucose fingerstick meters are not the most accurate or precise instruments. If your meter was off by 15%, your actual glucose could have been 85 (4.7), not 100 (5.6).
Congrats on your new D-tech. I’ve read so many good things about the Libre. Let us know how you’re doing with it in the days ahead.
thanks
i will let u know in the in the days 2 come how it is
In practice always add 25 on libre’s reading and you will have the right one.
Plus, Libre has quite a lag compared to e.g. Dexcom when the sugar is reading/falling, hence, if you don’t feel well - check the blood reading.
All glucose sensors are 15 min behind. They measure in the upper layer of the skin. There the sensor measures the glucose level in the interstitital fluid. If glucose is consumed it will be absorbed in the digestive system. Then it will enter the blood stream. From there it will be transported via diffusion processes into the upper layers. This takes time and therefore every glucose sensor can only tell you the glucose level from 15 min ago - not the current level. The trend arrow is a result of algorithms trying to derive future developments from smal changes in glucose levels. Here Abbott is conservative and sometimes their algorithm will exagerate trends to the low or the high side. But with some experience you can even dial your dosage based on the Libre numbers.
In general many users have this false belief that their meter is more correct than their sensors. The problem is that all meters are allowed to deviate 15% and older meters even more - from measurement to measurement. So even taking the same drop of blood from the same finger can result in two different results from the same meter. In my experience I had far more false results from glucose meters than from my libre. This also has to do with the fact that often we touch substances with our hand that contain some form of glucose or fructose. This residue on our fingers can cause additional deviation in addition to the technical deviation. At the end you should trust your feelings more than any device.
I find my libre to often read low. Particularly the first day, though sometimes that continues.
So I do some finger pricks to check the accuracy and how much lower it is reading. Typically I find it is about 10 points lower, after the first day.
I do find it very useful for monitoring trends in blood sugar, and there lies it’s greatest benefit. Much cheaper than dexcom, and gives real time trending.
I also like that I can enter exactly how much insulin I’m taking and when.
I do understand this is what is stated.
I can only say that our experience with the Dexcom G5 is that it is quicker than that. My suspicion is that “15 minutes” it just way too round of a number and that like so many other things, different people are different. Again, my suspicion, is that the “15 minutes” is based from a somewhat large population of people with the time rounded off to make a nice easy number to say.
Best way I found to see what the lag is? Wait for straight and level CGM. Eat 4 starbust in about 30 seconds. Time how long it takes for the CGM graph to jump. Then you have an idea what the lag might actual be for you. Dexcom only reports every 5 minutes so it might take a little work to get it down more precise but if you treat it like a game then you can get it down to the minute without excessive effort.
I don’t claim to have even the smallest understanding of the process. I just like to know the end results to be able to use the information provided.
For us - significantly quicker than 15 minutes.
Wow, that’s close. Sure beats blood-sucker metres.
Canada just got onboard with the Libre - pre-ordering only, with a 8-10 week time lag, so looking forward to buying local instead of shipping from Germany as I have had to do for the past two years.
Does anyone need a German/Dutch/Spanish Libre reader? Unused and reads in mg/dl instead of mmol/Litre. Just doesn’t have English … Happy to pass it on
I have run them in parallell for 2 weeks, testing the Blucon. G5 reacts quicker when the sugar is rising or falling quickly, but they even out after a while. Also, if the movements are not spiking up or down they work in quite a similar way, though with G5 being more reactive compared to the blood.
The Libre is a cheaper alternative so I think that this kind of variation can be tolerated.
I think the quicker reaction is just due to a different algorithmic evaluation of small variations. In other words small variations will be amplified to conclude that the blood glucose is rising. This would make the shown glucose number a kind of guestimated projection. Without further knowledge this is just guess work on my side. On the other hand I have experienced that even the Libre exagerated the numbers from the first rise from glucose tabs and later this leveled out far lower.
One difference between G5 and Libre. The Libre EU clearance states that the sensor has to be applied to the outside area of the upper arm. Inofficial spots can show much quicker reactions comparable to the G5 - the upper area of the breast area for example - although I would not recommend this due to the high likelyhood of hitting blood vessels.
Have you tried any other place yourself? The chest area is not my kind of thing, but I could move it around the arm if it would give better results.
Sorry for my late reply.
I have tried the hip and it worked well. But this location is in conflict with my injections and therefore I do not use it that often. With the thighs I had mixed results. Sometimes the additional pressure from the pants will reduce the blood flow in the sensor area causing more lag.
BTW: I can not contact ambrosiasys and their mail server for contact@ambrosiasys.com is technically down. Do you know what is going on with them?
No idea, I never send them emails. I am in touch with them via fb messenger (they asked for my feedback) and with Piyush via LinkedIn. I actually asked them today if they have any news re the release date of the next update. No response so far.
I got a reply from Ambrosia today, saying that the new version of the app will be released soon. They are finishing it.