Having a normal fasting blood glucose DOES NOT mean non-diabetic! In fact majority of diabetics have normal fasting glucose!!
This was discovered by Dr Joseph Kraft in the 1970s. He designed a test called the Kraft's Test which measures how insulin-resistant one is. Insulin resistance develops slowly over a period of decades. One can determine how insulin resistant one is using the kraft's test.
What is the Kraft's Test?
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1. Consume 100 gms glucose drink in the fasting state.
2. Measure serum insulin levels at 0, 0.5, 1, 2, 3, 4 hrs.
3. The pattern of insulin response to 100 gm glucose challenge determines how insulin resistant one is.
4. Stage-1 people are non-insulin-resistant (perfectly normal glucose metabolism) and stage-5 people are fully diabetic. People in stages 2,3,4 are progressively more and more insulin-resistant.
5. With proper treatment, a person in stage 4 will regress to stage 3, then stage 2 and then finally come to stage 1.