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C=peptide 1.5

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Hi all,


I was determined as type 2 in Feb this year, taking a few medicine, started low carb just a month ago, but my BP stopped going down recently. (about 108-126 fasting)

I wonder if I was LADA since I am below 30. Thus I asked for C-peptide test and the results is ard 1.4...the nurse said this is within normal range...

And I think it almost fell out of the normal range....


Can anyone give some more advise? Is 1.4 too high to be determined as LADA? THx

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Each lab will define their own normal range for C-peptide.


Additionally, a single C-peptide is of limited use - you need two; one fasting C-peptide, and a subsequent C-peptide taken 1 hour after a Glucose Challenge


It is the comparison between these two numbers that is most informative.


Fasting C-Peptide is simply a measure of how much insulin was produced by your body "recently", reduced by the amount your body has metabolized. Since each person's Basal rate of C-Peptide production is different, and their rate of clearance is also different (and affected by factors such as whether or not they have done vigorous exercise recently; whether or not they are recovering from an injury; what their cortisol levels are, etc).


However, this fasting value gives a baseline against which the subsequent glucose challenge C-peptide can be assessed.


This comparison allows a relatively accurate assessment of how much insulin is produced & released in response to a glucose challenge.


If this number is "low" (especially if you also show elevated blood sugar levels)

- your pancreas simply is unable to produce enough insulin (type 2 with pancreatic burnout; type 1; type 1.5; surgical/chemical destruction of the pancreas).


If this number is "high" and your bg levels remain normal

- you have insulin resistance, but it has not progressed to "full blown" type 2 diabetes


If this number is "high" and your bg levels also become elevated

- you have Type 2 diabetes


If this number is "normal" - then look at your bg in response to the Glucose Challenge.


Assuming you are talking about "nanno grammes per millilitre" (ng/ml)


Children <15 years are expected to have a fasting reading of between 0.4 - 2.2 ng/ml

Adults are expected to have a fasting reading of between 0.4 - 2.1 ng/ml


After a Glucose Challenge, you would expect a range of between 2.0 and 4.5 ng/ml


(but for example, a fasting reading of 0.4 should not jump to 4.5 after a glucose challenge unless the person is already (becoming) diabetic, even though both numbers are "within the normal range" - this is why having both numbers to compare is a good thing.)

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C-peptide in LADA can be anywhere within the normal range and below. T2s usually have normal c-peptides or ABOVE as their pancreas try to crank out more insulin to overcome the insulin resistance. When you say your BP stopped going down recently, did you mean your BG (blood glucose) levels stopped coming down? LADA is confirmed by a positive GAD65 antibody test. There are also 2 other antibodies that may be positive as well. There is an autoimmune component to T1 as well as LADA, which is a slow onset T1. See if you can get them to do a GAD65 antibody test. It's a blood test and you don't need to fast for it. If positive to any degree, you are a T1 and should go on insulin as soon as possible to preserve some beta cells. Oral medication should not be given to a T1.

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Many type 2's have even lower c-peptide because their pancreas has lost beta cells. The difference is a Type 2 will test negative on the Antibody tests. So if you are concerned get a set of Antobody tests

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