Freestyle libre reading vs lab result

Posted by jdiakiw @jdiakiw, Nov 5, 2020

As I sat while the lab technician drew blood for testing I scanned my freestyle libre scanner. My scanner read 6.5 mmol/l. When the blood results came from the lab, the blood sample reading was 9.1 mmol/l. Is that a normal difference or can I not trust my ‘freeStyle ‘ system ?

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I do not know about the freestyle libre scanner because I have not needed to use one, but I am wondering if the number posted is a "range" number rather than an actual blood sugar number average over three months. I am thinking there is a difference. The basic science is that if you eat less carbs and still eat a balanced diet, the numbers will come down. I have been at this for 15 years and have been successful without a mechanical aid other than the stick style tester and it doesn't bother me much. It's the food and the eating and the exercise that make improvement. Dorisena

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Hi , I also use Free Style Libre , there is a 1-2 points reading , it’s usually lower than testing with blood .

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Can’t get accurate blood reading from Libre !

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@dtkbac687800

Hi , I also use Free Style Libre , there is a 1-2 points reading , it’s usually lower than testing with blood .

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If you aren't willing to change your eating habits to less carbs, the test is just playing with your mind about your health. It isn't going to fix your blood sugar problem and it is discouraging to not see success in the numbers or to see numbers that are unusually low. Using pills to manipulate a high carb diet will not lead to good success and feeling well. Committing to a better diet and lifestyle for your body is the answer and it gets easier with time and effort. I consider myself a well person who provides what my body needs for good metabolism.
I still work on the weight issue as do my family and friends. High blood sugar numbers can lead to added health problems and an early death. My late husband died at age 71, obese, hard of hearing, with declining eyesight, with dementia, with hands shaking very morning, with uncontrolled diabetes, a cancerous tumor growing up his spine, and in terrible denial about his health. We don't want that life and we want a positive attitude about living with our loved ones and friends. He was addicted to opiods and was an alcoholic who drank every two hours but still drove every day. We did not ride with him. But he was free to do what he wanted and denied he had cancer to the end, lying is a hospital bed, hooked up to a pain pump and paralysed. He didn't eat for six weeks. That is what motivates me to try to be supportive with this friendly group. We are learning to care for our bodies in the best way possible. Dorisena

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I forgot to report that when I used the home test for my A1C I got lower scores than when I tested at the lab, so I am scheduled for another lab test now along with my annual thyroid level test for my Synthroid treatment. My cancerous thyroid was removed years ago. I don't rely on the home test for testing my progress and I have a lower goal to achieve than the doctors recommend. i stay motivated to try to reach an optimum goal. Dorisena

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The lab will most likely show the A1c reading which is roughly an average of the past 3 months. The libre system takes a snapshot in time (assuming it is calibrated correctly); for this reason, I find simple testing is better for me with type 2 diabetes, as I take the readings at approximately the same time ever day to judge the overall trends. Your blood sugar can and will change significantly throughout the day, particularly the hours after eating.

In my humble opinion, if you are not taking insulin, the libre system is best left for those with type 1 diabetes unless directed by your physician. (But Abbott does appreciate the extra money!)

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Thanks, Howard, I appreciate understanding these technologies better even if I don't use them. I wanted to get the blood pressure watch for monitoring and noticed that even the web site said that one particular model was not always accurate. I want to get the heart monitor that is advertised right not but my son asked me what I was going to do with the numbers since I don't have an app to send it to a doctor for review. I decided to save my money and go to for medical help when and if I have frightening pain since I live close to town. My emergency squad site is less than two miles away. I pay taxes for that service and have a system for them to get into my locked house. I do use my blood pressure cuff every day as directed by my doctor. Dorisena

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@howardm

The lab will most likely show the A1c reading which is roughly an average of the past 3 months. The libre system takes a snapshot in time (assuming it is calibrated correctly); for this reason, I find simple testing is better for me with type 2 diabetes, as I take the readings at approximately the same time ever day to judge the overall trends. Your blood sugar can and will change significantly throughout the day, particularly the hours after eating.

In my humble opinion, if you are not taking insulin, the libre system is best left for those with type 1 diabetes unless directed by your physician. (But Abbott does appreciate the extra money!)

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@howardm I am not familiar with the Libre system, I test using a regular monitor. My A1c is always relatively low, often under 5, the last test, about a month ago, it was 5.6 so my endocrinologist does not insist that I test daily.

He has told me to test at different times of the day, after different meals though. I was always testing after breakfast. I think it does make more sense to test after different meals because it can change greatly depending on what you eat. I almost always have oatmeal for breakfast and later in the day, my meals tend to have fewer carbs.

Sometimes I wonder if I really am still diabetic but my endocrinologist has said once you have it you are always considered to be diabetic.
JK

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@contentandwell

@howardm I am not familiar with the Libre system, I test using a regular monitor. My A1c is always relatively low, often under 5, the last test, about a month ago, it was 5.6 so my endocrinologist does not insist that I test daily.

He has told me to test at different times of the day, after different meals though. I was always testing after breakfast. I think it does make more sense to test after different meals because it can change greatly depending on what you eat. I almost always have oatmeal for breakfast and later in the day, my meals tend to have fewer carbs.

Sometimes I wonder if I really am still diabetic but my endocrinologist has said once you have it you are always considered to be diabetic.
JK

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I have the same concerns, JK, because I just did a home A1c test before I go to have a lab test. It showed 5.7 and the previous home test was also much lower than my regular lab test. Yes, I am still diabetic because last week my granddaughter and I baked peanut butter cookies, and since I have not had a cookie for a very long time, I had to eat two of them. I also ate a bowl of squash soup from Panera Bread. Two hours later my blood sugar was 231 so I know that I still have sugar spiking problems. The cookies had both regular sugar and brown sugar in them, in addition to white flour and lots of butter. which does slow the sugar spike somewhat. I feel good that lowering the AiC over time will help prevent the complications that come from uncontrolled blood sugar problems. Yes, I think we will have to work on the problem the rest of our lives but perhaps the insulin in our bodies might learn to work more efficiently. Dorisena

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@howardm

The lab will most likely show the A1c reading which is roughly an average of the past 3 months. The libre system takes a snapshot in time (assuming it is calibrated correctly); for this reason, I find simple testing is better for me with type 2 diabetes, as I take the readings at approximately the same time ever day to judge the overall trends. Your blood sugar can and will change significantly throughout the day, particularly the hours after eating.

In my humble opinion, if you are not taking insulin, the libre system is best left for those with type 1 diabetes unless directed by your physician. (But Abbott does appreciate the extra money!)

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I was surprise when my scanner showed me 6.1 mmol/l. At 11:30 as my blood was drawn. The lab test came back showing
9.1 glucose fasting and AIC 9.7. My time in target on my freestyle monitors shows me over 70% time in target ever since I got my system. I do take 10mg of insulin in my belly daily

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