This test is crucial for understanding how well the pancreas' beta cells are working. It's especially helpful for distinguishing between type 1 and type 2 diabetes, monitoring the health of pancreatic or islet cell transplants, and identifying the cause of low blood sugar due to high insulin levels. This could mean finding out whether the body is producing too much insulin on its own or if insulin is being introduced from outside the body. Additionally, the C-Peptide test is more reliable than direct insulin measurements for certain assessments because it's less affected by blood sample handling.