What are the optimal levels for fasting free & total insulin for someone without diabetes?

Normal insulin level: Normal fasting insulin level is less than 25mlU/L. Insulin levels normally rise after meals in order to prevent prolonged hyperglycemia. High fasting insulin levels cause hypoglycemia.

Fasting-25miu/L : This is equivalent to 174 pmol/L. testing is more vital in the dx of Type1 diabetes mellitus that tends to be seen more frequently in children,in assciation with antibodies against islet cells of the pancreas.