Diabetes Epidemic & You must be studied rather than read. What is the earliest laboratory diagnosis of clinical diabetes? The very earliest laboratory diagnosis of clinical diabetes is by oral glucose tolerance with insulin assay. This is the essence of my textbook: Diabetes Epidemic & You. Hyperglycemia, unfortunately for many, persists historically as the earliest diagnosis. The oral glucose tolerance with insulin assay is an empirical laboratory procedure. It is multiple biochemical biopsies that are dynamic. Credit must be given to Dr. Yalow and Dr. Berson who pioneered the behavior of iodine-131 labeled insulin. Their study led to the development of radioimmunoassay for plasma insulin. For this procedure development in analytical clinical chemistry, Dr. Yalow shared a 1977 Noble Prize in medicine with Dr. Berson. It was not until 1970 that Pharmacia Diagnostics AB, Uppsala Sweden, made available Pharmacia Insulin RIA, based upon World Health Organization standards for the quantitative measurement of insulin serum. Pharmacia Insulin RIA was applied to Dr. Joseph R. Kraft’s oral glucose tolerance, becoming a routine procedure in 1972. Dr. Kraft’s initial 500 tolerances confirmed Dr. Yalow and Dr. Berson’s findings of increased insulin (hyperinsulinemia). Dr. Yalow and Dr. Berson’s insulin responses were unclassified while Dr. Kraft’s 500 examinations identified and classified five distinctive dynamic insulin patterns: Pattern 1 (euinsulinemia) is normal glucose tolerance; patterns II, III and IV, (hyperinsulinemia) is type 2 diabetes; and pattern V, low response (hypoinsulinemia) is type 1 diabetes potential. The very earliest diagnosis of diabetes is neither by fasting blood sugars nor by glycated hemoglobin, but only by insulin assay with normal glucose tolerance as affirmed in this text. Dr. Kraft’s 14, 384 oral glucose tolerances with insulin assay with ages ranging from 3 to 90+ years have substantiated the very earliest laboratory diagnosis of diabetes. This resource of 14, 384 oral glucose tolerance with insulin assay is unequalled in world medical publications. The very earliest diagnosis of pre-diabetes is hyperinsulinemia, type 2 diabetes identified by insulin assay with normal glucose tolerance. Deductive reasoning will affirm the very earliest laboratory diagnosis of type 1 and type 2 diabetes. When coupled with specific therapy, the worldwide diabetes epidemic can be arrested and reversed.