C-peptide test question

Any thoughts on what these c-peptide numbers mean in terms of my lada/ or type 1 or 2 status?
My fasting c-pep was 0.46 ng last year and later it was 0.53. I just did a post prandial c-peptide test which came back at 1.61 ng. This was about 90 min post meal. It shows within the “normal” range of the lab (which is .8 to 3.15). I am waiting for anti bodies, but one year ago I was mildly positive for GADA. - I am struggling with my BG control.
Yes I will ask my doctor but curious for other thoughts as I wait for the appointment. Thanks!!

Yes your numbers look pretty normal.
Usually if your fasting c peptide is low, it suggests type 1.
If your 2 hrs PP is high it strongly suggests type 2.

You are normal for both. But it’s not the whole story.

If you have positive antibodies then eventually you will lose beta cell function and need insulin.

Personally I didn’t get good control until my beta cell function was totally gone and I was getting zeros for my cpeptide.

The little bit of insulin production made it harder to control.

For me it took only about 6 months to be totally done.

The older you are the slower the cell loss is

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See what the tests say with your doctor. With the normal range c-pep, it’s a good bet you’re not T2. I would expect it to be raised, because of insulin resistance.

what was the BG with the post prandial c-pep? If you had high BG with it. it may mean your pancreas couldn’t put out anymore insulin

What BG issues do you have?

That’s true for us type 2 DMs who have diminished insulin secretion. Since I began MDI, I have had to do a lot of tweaking with the blessing of my doctor. The bolus rapid u:carb is steady, but basal is more of a problem.

I was having a real problem doing any kind of endurance exercise as 15 minutes of cycling or brisk walking would cause BG to dive.

My doctor suggested I cut the Metformin I take by half. This has improved morning diarrhea and I think allowed for a better glycogen response from the liver.

I’ve been able to do 4 rides of 2+ hours while staying in range, between 90 and 150mg/dl.

Gotta keep learning to keep the little gray cells happy.

The fasting c peptide numbers I noted earlier were below normals and with high sugars at the time. With mild GADA they said type 1 lada and prescribed multiple daily injection and bass. But another doc says “you are still making some insulin so you should be treated as type 2”.
My new tests shows no antibodies.
I am usually unable to bring down any high sugar (or it takes all day) without bolus.
My 1.6 ng c peptide result is likely the most I can make as it was after meal with 240 sugar. I read elsewhere that you should be over 3 ng after meal.

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Find another doctor !!


You are on insulin. Does a T1 have advantages, over T2? Given you had a positive antibody test before. It would be diagnosed LADA, late onset T1

One doc would put me back on type 2 meds. Maybe in addition to basal. I guess might as well try. Why not experiment

A GLP-1 and basal insulin may help in either case. LADA or T2. I wouldn’t take a Sulfonylurea and such.

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Thanks. Do you know , can you add a GLP-1 to both basal and bolus? Or is it just to be added to basal?