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C-peptide.
Normal C-peptide levels for a fasting test are generally considered to be anything between 0.5 nanograms (ng) per millileter (ml) and 3 ng/ml, although people who do not have diabetes may occasionally stray out of this range. The following is a range of C-peptide values in people without diabetes, as compiled by Endocrine Sciences, Inc., a California-based laboratory that conducts the test. It should be noted that, in some cases, subjects fell below the normal range of C-peptide values, but were still not found to have diabetes. The range of values may also vary according to what lab your health care practitioner uses.
Children (< 15 years old) 8:00 a.m. fasting: 0.4 to 2.2 ng/ml
Adults 8:00 a.m. fasting: 0.4 to 2.1 ng/ml
Two hours postprandial (after a meal): 1.2 to 3.4 ng/ml
Two hours post glucose load: 2.0 to 4.5 ng/ml
Although anything less than these numbers is generally an indicator of type 1 diabetes, values within the normal range can mean different things.
"Type 2s with insulin resistance could actually be making more insulin than a non-diabetic slim person," says Richard Bernstein, MD, FACE, FACN, CWS, of the Diabetes Center in Mamaroneck, New York. Values on the lower end may also indicate a honeymoon phase of type 1, when insulin production is slowing down but has not yet ground to a halt.
Bernstein also points out that even in type 1s, a positive C-peptide test should be a source of optimism.
"Of all my patients, I only have two who don't make any C-peptide, and I'm one of them," Bernstein says. He says this proves that most type 1s still produce at least some insulin and raises the possibility that therapies like beta-cell regeneration may eventually restore normal BG levels.
Categories: Diabetes, Diabetes, Endocrinology, Insulin, Insulin Resistance, Other Lab Tests, Pre-Diabetes, Type 1 Issues, Type 2 Issues
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Comments
My daughter is 6 yrs. old and just diagnosed insulin resistant c- peptide fasting of 4.6 and was put on metformin.. It has been a long road but our pediatric endocrinologist found what 2 pediatrician said to be our fault (why she was gaining weight only eating 800 calories a day) if you feel uncomfortable with any thing they say find someone else your instincts are always right
MY C-PEPTIDE IS 1, MY A1C IS APPROXIMATELY 6.5, AND MY AVERAGE BLOOD SUGAR IS 114. I WORK OUT AND MAINTAIN MY WEIGHT, AND I TRY TO EAT A HEALTHY DIET. I AM ON INSULIN-4 UNITS EVERY NIGHT. IS THERE ANYTHING ELSE I CAN DO TO MAINTAIN MY HEALTH. ANY INFORMATION IS GREATLY APPRECIATED.
my c peptide test results was 1.4 (mg/dl).
How does this convert to (ng/ml)??
MY C-PEPTIDE IS HIGH 4.5 WHAT DOES THIS MEAN
I'M A DIABETE, I TAKE INSULIN. MY BLOOD TEST SHOWED I HAVE A 5.4 C-PEPTIDE READING, DOES THIS MEAN I COULD HAVE A TUMOR IN MY PANCREAS. THANK YOU
MY SON HAS A C-PEPTIDE OF 3.8. HE DID NOT HAVE A GLUCOSE TOLERANCE TEST. I WOULD HAVE EXPECTED THAT BOTH TESTS WOULD HAVE BEEN DONE TOGETHER. HIS IS MISSING THE DISTAL PORTION OF HIS PANCREAS. (3/4THS OF THE PANCREASE IS MISSING) ANY COMMENTS ARE APPRECIATED
I am presumably type I. 40u/day Latus + humulin at age 44. Diagnosed type I age 19. I have never been tested for c-peptide. I wonder why I haven't. Why has no one ever suggested this for me? What do you know of c-peptide therapy? Thank you for any help you can offer. Sharla
Why can't c-peptide be done on a random urine sample? Does it always have to be done on a 24hr sample or blood?
Thanks,
peter
I just recently had a c-peptide test and my results were 13.5. Can someone tell me what this means for me now? I am already on the 50/50 quick pen and take 1000mg of metformin twice a day?
Does all above indicate that Diabetic type2 with insulin resistance have higher C. Peptide level and so higher insulin secretion? If this is the case, will it not be better to make better use of insulin? In some consideration, higher insulin exposure can also be related to downregulation of insulin receptors, decreased insulin occilation & degradation. Persisting higher glucose levels may also cause hypoglycemia type events even at higher than normal glucose levels. As such, can it cause hypoglycemia unawareness? I think C Peptide is not related to injected insulin. All these issues may need proper attention.
I just got my C-peptide value but don't understand it.
The Dr. wrote down on my results that the range for C-peptide
is between 297 - 1419. I came it at 792.
So what does that equate to? I know it's in the normal range.
I was diagnosed as Early Type 1. I'm 42 years old.
I'm taking 30 units of Lantus in the morning.
And taking 8 units of Novalog per meal of 60g carbs.
My numbers are good and range from an average of 100 before meal and 140 after.
But I'm wondering if I'm more of a Type 1.5 or just that we caught my Type 1 so early that my C-peptides show that I'm still producing some insulin.
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