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C-peptide Levels?

MrsGruffy

MrsGruffy

Well-Known Member
Messages
147
Location
Launceston, Tasmania
Type of diabetes
Type 2
Treatment type
Tablets (oral)
I just got my latest bunch of blood results and my fasting c-peptide level was 1.9 nmol/L (range 0.5 - 1.0) which equates to 5.7 ng/mL. I've just been consulting Dr Google, and I can't find a lot of information on what that might mean. So I was wondering if any of you T2s have a high c-peptide level? Is it maybe normal for T2s to have high levels like mine? My fasting insulin was 23 mU/L (range 3 -25 mU/L)
 
Hi my c-peptide was .48 nmol/L where the range was specified as .34 to 1.8 at that particular lab. So your number looks high, to my eye. I thing the mean for non diabetics is around .62. Dont know if thats any help.
 
The figure I've seen as ideal for fasting insulin is around 6, so yours still seems to be pretty high. Maybe the higher c-peptide goes along with the higher insulin level? Not really sure though - getting both tests seems unlikely given my good A1c levels. I'm surprised you were even given the tests given how tick-box GPs are with most tests these days. I've lost count of the "that's not on my list" and blank stares if I mention any out of the ordinary tests to mine.
 
I asked to have the tests done because my DE was wondering why I'm so hyper responsive to carbs.. I thought perhaps my insulin levels were very low, which they're not, so that's a huge relief. I've actually never had any trouble getting tests done that I want done, and I've spent years advocating for other people with HCPs while working in disability, mental health and later in palliative care. I'm really getting a hard time about my cholesterol levels, and I have to admit, it's got me a bit nervous. I was told to go home and familiarise myself with the signs and symptoms of heart attack and stroke on the heart and stroke foundation's websites. My grandma had her first heart attack in her late 40s, then eventually a couple of very debilitating strokes and further heart attacks. She spent the last 20 years of her life a very sick woman. Her daughter, my mum, died suddenly at 43. The heart issues are all through both sides of the family, so I am really trying to make sense of what I've been reading and watching on the youtubes compared to the advice I've been getting from my HCPs - totally contradictory. Anyway, the c-peptide thing being quite high - I was hoping perhaps it would be a clue about what might be going on with me. I have really good BCGs now, but that's because I'm eating one meal a day which is well less than 20 g of carb. Even so, this last week or so, the 2 hours post prandial is creeping up into the 6s. Prior to this, it has stayed well under 6. Now I know the numbers are fine, and I'm a newbie, but I would not expect to see much movement at all from green veg, meat and olive oil. A sliver of cake (less than 20 g just to taste a new recipe I made for Mum to make sure I wasn't poisoning her) and I got a 2 hr pp of 14ish. I'm being very strict overall, but I guess I don't know enough still to know whether this is just normal four months on. I think my next move is to get a CAC score and then decide what else I can do to improve things further. It all feels rather miserable, to be really honest. My last A1C was 5.2% which is a big improvement on 8.9%.
 
Have you thought of reaching out to Dr Gary Fettke or his wife Belinda since you're in Tassie too? I think they have/had a lifestyle clinic that helps with diet etc. and both know a lot about Type 2 and LCHF. Might be worth considering. If you're on Facebook, you could probably post on the NoFructose group.

I see by your profile that you're taking metformin, but what dose are you on? Can you also remind me about whether you've started fasting yet? I'm surprised that your insulin is still so high after 4 months of low carbing, but like I said, I'm no expert.

Tagging @bulkbiker as he's had insulin tested and may have more info than I know about it.
 
Think the fact both your fasting C-Peptide and Insulin are very high give pretty conclusive evidence of your insulin resistance - i.e your pancreas is working overtime to produce the insulin needed to counteract all the sugar flowing around your body but for some reason the body has built up a resistance to it or the insulin just isn’t working as it should.

I’m in the middle ground of being classsed as Type 1.5 at present yet have normal fasting C-Peptide and Insulin - usually the red flag for type 1 / 1.5 is low indigenous C-pep & insulin.... so at least you can be happy that you are nowhere near Type 1 and your pancreas is still producing!

I guess it’s time to try and cut all carbs - as you are doing - and hope the pancreas gets a rest and starts producing better quality insulin again which will help take the edge of those carbs. I had a similar experience when after a month of being diagnosed and cutting out every non essential carb I could I had a piece of millionaires shortbread and I was up at 10 2 hours later! Sucks ... just gotta hope the body will steady the ship and start dealing with insulin and carbs as it used to again
 
MrsGruffy said:
I asked to have the tests done because my DE was wondering why I'm so hyper responsive to carbs.. I thought perhaps my insulin levels were very low, which they're not, so that's a huge relief. I've actually never had any trouble getting tests done that I want done, and I've spent years advocating for other people with HCPs while working in disability, mental health and later in palliative care. I'm really getting a hard time about my cholesterol levels, and I have to admit, it's got me a bit nervous. I was told to go home and familiarise myself with the signs and symptoms of heart attack and stroke on the heart and stroke foundation's websites. My grandma had her first heart attack in her late 40s, then eventually a couple of very debilitating strokes and further heart attacks. She spent the last 20 years of her life a very sick woman. Her daughter, my mum, died suddenly at 43. The heart issues are all through both sides of the family, so I am really trying to make sense of what I've been reading and watching on the youtubes compared to the advice I've been getting from my HCPs - totally contradictory. Anyway, the c-peptide thing being quite high - I was hoping perhaps it would be a clue about what might be going on with me. I have really good BCGs now, but that's because I'm eating one meal a day which is well less than 20 g of carb. Even so, this last week or so, the 2 hours post prandial is creeping up into the 6s. Prior to this, it has stayed well under 6. Now I know the numbers are fine, and I'm a newbie, but I would not expect to see much movement at all from green veg, meat and olive oil. A sliver of cake (less than 20 g just to taste a new recipe I made for Mum to make sure I wasn't poisoning her) and I got a 2 hr pp of 14ish. I'm being very strict overall, but I guess I don't know enough still to know whether this is just normal four months on. I think my next move is to get a CAC score and then decide what else I can do to improve things further. It all feels rather miserable, to be really honest. My last A1C was 5.2% which is a big improvement on 8.9%.
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HI thanks @Indy51
I have had my fasting inulin tested twice but don't know much about the C_peptide test as so far as I know mine has never been looked at. so never done any research on it. Your fasting insulin does look a bit high so maybe a bit of fasting and keto would assist. Not sure I feel comfortable saying much more than that. Sorry.
 
Indy51 said:
Have you thought of reaching out to Dr Gary Fettke or his wife Belinda since you're in Tassie too? I think they have/had a lifestyle clinic that helps with diet etc. and both know a lot about Type 2 and LCHF. Might be worth considering. If you're on Facebook, you could probably post on the NoFructose group.

I see by your profile that you're taking metformin, but what dose are you on? Can you also remind me about whether you've started fasting yet? I'm surprised that your insulin is still so high after 4 months of low carbing, but like I said, I'm no expert.

Tagging @bulkbiker as he's had insulin tested and may have more info than I know about it.
Click to expand...
Thanks Indy - yes I have thought about reaching out to Dr Fettke.. just have to summon up the courage to make contact. I follow them around the internet traps! I have been doing LCHF for 12 weeks now, and for the last 3+ weeks, after a 3 day water fast, I have dropped down to 1 LCHF meal a day - green veg, fat and meat. I felt very poorly on day 3 of the water fast, with diarrhea and just incredibly tired, so I stopped it then. I have been super strict with myself with the exception of a very small sample of date and nut loaf I made for Mum because the dates were a bit old and I wasn't sure how it would go. Every time I've had even a small amount of carb, my BG goes up a LOT. I'm on 1000mg of metformin twice a day. It has no ill effects on me except for a slightly gurgly tummy from time to time.. high motility apparently. I supplement with a multivitamin, magnesium, vit D and fish oil every day. My blood ketones are consistently 1.6.
 
My experience of a 3 day fast was very similar. I'm quite happy with my 16:8 routine for the most part.

How is your fasting BG level going? For me it was the very last to come down and even that didn't happen until after I started 16:8, even though I wasn't at my lowest weight at the time.

The high spikes after carbs when you're adapted to low carb is not uncommon. I once had a nightmare experience after eating a single mango. I'm a bit better now than I was, but likewise took quite a long time - and again only happened after I adopted 16:8.
 
Fasting BG this morning was 5.9. A bit higher than usual mid 5s. It has come down since I started OMAD. It was in the 6s on LCHF most mornings. I'm guessing I need to hurry up and wait!
 
MrsGruffy said:
Fasting BG this morning was 5.9. A bit higher than usual mid 5s. It has come down since I started OMAD. It was in the 6s on LCHF most mornings. I'm guessing I need to hurry up and wait!
Click to expand...
I think it takes a while to come to terms with a change in lifestyle being exactly that, for "life". So there's really no timetable :D
 
It can take many years of a low-carb diet along with a lot of resistance training before insulin resistance returns to normal levels hence I would not expect fasting insulin or C peptide to be normal in someone with type 2 diabetes who has only been doing low carb for a few months. Professor Tim Noakes has posted a little about this on Twitter.

Remember c-peptide is just another way of measuring how much insulin the body is making it is used as a test because it separates out the effect of insulin being injected and naturally made inslin.
 
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