Feedback: If anyone wants to have a meaningful interpretation of their glucose levels and its history, one must look to the range of possible causes. One of the most significant factors is Pancreas functionality. Beta cell dysfunction can limit insulin production by the pancreas, and although there is no present test for pancreas insulin function, the pancreas does throw off C-Peptide in the process of. insulin production, and this peptide can be measured, giving a reasonable accurate measure of Pancreas insulin production.