I was wondering, according to Dexcom, their CGM measures the interstitial fluid. Does the FreeStyle Libre, currently unavailable in the US, measure blood glucose ? or does it measure interstitial fluid?
How would this be possible short of being implanted in a vein or artery? Wouldnât it just clot over anywhere else and maybe even there?
Preventing it from clotting is the huge challenge. Maybe something like the mechanical leach? Theyâve been working on that for post surgery to reduce fluid pressure after tissue reattachment surgeries and skin grafts.
I donât know. Itâs definitely difficult, but I donât think itâs impossible.
I suspect the question becomes whether the substantial trouble is justified by the potential incremental benefit
Libre measures ISF as well.
This is from the Freestyle Libre website:
âScanning the sensor to obtain glucose values does not require lancetsâ 404 - Page not found | FreeStyle Blood Glucose Meters
I suspect that âscanningâ in this context means waving the Libre receiver near the sensor to capture a reading. âDoes not require lancetsâ likely promotes the Libre design feature that no calibration fingerstick is required.
Correct. Wasnât sure of the context of the post thatâs why I asked.
It would seem that the Libre sensor is measuring something and the receiver captures a reading. The question is : What is the sensor measuring? blood glucose?
In the case of the Dexcom, the sensor is measuring ISF. A fingerstick calibration is necessary to tell the Dexcom that the ISF value measured by the sensor corresponds to a BG value of x.
The Libre ads does not seem to indicate the need for a fingerstick. What is it measuring?
Hey Allen, Great to hear about your success using Afrezza! We had a learning curve at first too, but your results are now better than ours! Congratulations!
Regarding lung cancer fears. I am a cancer biologist and for me my greatest fear regarding cancer of all types in diabetics is high blood sugar. High blood sugar is the reason diabetics have a statistically higher incidence for all cancers. The reason is Cancer cells have a disproportionate reliance on sugar for a food source. If you are interested you can look up the Nobel Peace Prize winning work of Otto Warburg (The Warburg Effect). This effect is why radio labeled sugars used in pet scans will preferentially light up cancer cells. Cancer cells MUST have sugar, and lots more of it than non-cancerous cells. Much attention has be brought to concerns about hyper-insulinemia and its perceived link to cancer. The point that is missed is the only reason the body would have high insulin levels is because your sugar is high. Which came first the chicken or the egg? The fact is only SUGAR itself has been conclusively linked to a pro-cancer growth environment. Good luck to you! Continued good health!!
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The Libre sensor is inserted into subcutaneous tissue and not aimed at blood vessels. There is no continuous glucose monitoring device available to consumers that measures blood glucose directly. They sense changes in the interstitial fluid that correspond to blood glucose numbers. CGMs and Libreâs flash glucose monitoring system measure blood glucose indirectly.
Fingerstick meters, of course, measure blood glucose from blood but cannot give a continuous flow of readings.
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As I mentioned above the Libre is still measuring ISF. See link below:
Sensors are factory calibrated.
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Thank you @Vibes121 for all that info! It is very much appreciated. I definitely would have a hard time giving up Afrezza now as it has made life SO much easier. Now that I have the tools, the only thing left is for me to get better with my bad habits of eating too much junk and laziness. 
Thank you and I wish you the best of health and I hope you and your family have a wonderful holiday season.
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Itâs awesome to see your success. We like yourself had a learning curve with it. It once you understand how to use it, there is nothing better! Best of luck to you!!
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I convinced my endo, finally, to at least let me try Afrezza. I am waiting for the pharmacy to order the Titration Pack. Looking forward to trying it when :
- I eat out - and the meal/food is difficult for me to estimate the carb count and I have dessert.
- I eat pizza - which is very rare.
Iâm excited and looking forward to reporting back to the group my experience.
The best comparison would be keeping the food constant and varying the insulin type so the difference between 
and Afrezza is known better?
And that also would make titration easier and then venture out to uncharted waters?
Atleast thatâs my plan
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Just remember itâs all about timing much more so than with injected⌠that is 90% of the learning curve⌠it isnât hard to figure out how to take more or less as needed
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Yes.
I will test frequently to find the time at which point the BG starts to rise. Then I drink a some water, inhale the Afrezza, drink some water.
@Sam19- When you first started to use Afrezza, it was all about learning the timing- when is it best to take Afrezza⌠IIRC, you wanted to determine the point at which your BG began to rise. To avoid hypo, one should not take Afrezza until there is a rise in BG.
To learn the best time to take Afrezza for the individual, it is important to find out WHEN the BG begins to rise. This may sound like a stupid question, Iâll ask anyway: When you set your time to â0â the starting point of BG measurements, is that immediately before you eat your first bite? Do you then continually measure BG as you continue to eat your meal?
The follow up questions are:
If the meal is 1 hour, the food from the beginning of the meal, time=0 start to affect BG earlier than the food eaten at the end of the meal. The food at the end of the meal, time = 60 minutes will affect BG later, at time=60+, whenever that may be. If BG starts to climb at t=20 minutes, part way through the meal, and one takes Afrezza, it will be out of the system 60 minutes later, t=80 minutes. This is assuming the Afrezza is out of the system in 60 minutes.
What insulin will take care of the food that was eaten at t=60?
If the meal lasts awhile, say 1 hour or more, would you need multiple doses of Afrezza?
If the meal contains food that take awhile to affect BG, would you also require multiple doses of Afrezza?
This is assuming that Afrezza acts quickly and is out of the sytem quickly (say 60 minutes).
Things like that are going to vary from one person to the next and also with what youâre eating⌠thereâs not a precise formula for great success with it just give it a try and adjust as needed
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