Looking for early signs of type 2 diabetes usually involves measuring blood glucose - either fasting or after drinking a glucose load. However, this misses a much earlier sign - elevated insulin, signalling insulin resistance (i.e. the main abnormality in type 2 diabetes).
Here's a long and fascinating post on a true pioneer of this topic, Dr. Joseph Kraft:
Dr. Jeffry Gerber: Diabetes is a Vascular Disease - More on Joseph R. Kraft, MD
