Low C-peptide values cannot be recovered from type 1 diabetes, but may be recovered from type 2 diabetes. Type 1 diabetes is an abnormal metabolism of nutrients caused by autoimmune destruction of pancreatic beta cells. Since type 1 diabetes is usually caused by a combination of genetic and environmental factors, the low C-peptide values caused by type 1 diabetes, not only in the fasting state, but also when stimulated by glucose, are still low and usually cannot be recovered. Type 2 diabetes, also known as non-insulin-dependent diabetes, is usually caused by insufficient insulin secretion known as hyperglycemic toxicity, a self-protective measure taken by the pancreatic beta cells. If the disease is of short duration, C-peptide values usually recover gradually after oral hypoglycemic agents. In addition to medication, lifestyle interventions should be given to keep blood glucose in a good range. For patients with diabetes mellitus, in addition to the need to give the appropriate medication under the guidance of a professional doctor, in the daily life also need to do a good job of dietary control, and at the same time should be combined with the individual physical condition of the appropriate exercise.