Beta cells

Happy new year everyone! Just a quick question, is there any test that measures the efficacy of your remaining beta cells in producing insulin? (assuming you are type2). I heard of a c-peptide test. Has anyone had this done?

If you're not on insulin, they can measure you insulin levels to see how much insulin you're naturally producing. However, once you're on insulin, they have to measure your c-peptide levels to determine how much insulin you're producing naturally (because lab tests cannot distinguish between insulin you've injected and insulin your body makes naturally).

C-peptide is basically the molecular precursor to insulin. When the human body makes insulin, it first produces c-peptide and then, due to some molecular process that I don't really understand, the c-peptide splits and some of it goes off to produce insulin (I think that's how it works, but someone correct me if I'm wrong!) So, by measuring c-peptide, you can basically tell how much insulin you're producing naturally.

C-peptide levels are often taken in order to distinguish between type 1 and type 2 diabetes. People with type 1 diabetes have low to non-existent levels of c-peptide because their pancreases (pancrei?) aren't making any insulin. People with type 2 diabetes have normal to high levels of c-peptide. People with type 2 diabetes make insulin, but due to resistance, their bodies cannot use the insulin effectively.

Did you have your c-peptide levels checked at diagnosis to determine that you were type 2?

C-peptide is actually a connecting peptide . . . C for connecting. The precursor to insulin is proinsulin consisting of an A-chain and B-chain as well as a C-peptide connecting the two. The C-peptide is then "cut off" leaving an A and B chain off insulin. By measuring the C-peptide levels a general idea of can be determined of the patients ability to make insulin. This test results thou have a wide range of acceptable levels even in non-diabetics and are really as "useful as a gas gauge" . . . at either end of the extremes, that is very high or very low levels of C-peptide. It also helps to have an idea what one has been eating before hand as one would expect C-peptide levels to be higher after a meal versus C-peptide levels when fasting. Another facotor as well is the half-life of C-peptide as it is cleared from the body.

As for having it done, I've never requested it and I can't recall if it's ever been done. Besides, at this point I've been using insulin so long what's the point in knowing . . . the results woudn't change anything.

The c pep test is the answer. Many type 2's eventually lose the ability to make any insulin hormone. If you are type 2 for a long time, it may be best to check on one's ability to produce the hormone.Then it's insulin time, and that's not so bad.