Experts have reached international agreement on the blood sugar thresholds for diagnosing diabetes. Because blood sugar levels tend to rise steeply after a meal, for example, the thresholds also depend on how long ago you last ate.
Glucose tolerance test
The oral glucose tolerance test (OGTT) is used to measure how well the body can process a larger amount of sugar. First, you drink a glass containing water with 75 grams of dissolved sugar. This makes blood sugar levels rise, but they should usually go back down rather quickly. Diabetes is diagnosed if blood sugar levels are still above 200 mg/dL (11.1 mmol/L) after two hours.
Random glucose test
Petersmann A, Müller-Wieland D, Müller UA, Landgraf R, Nauck M, Freckmann G et al. Definition, Classification and Diagnosis of Diabetes Mellitus . Exp Clin Endocrinol Diabetes 2019; 127(01): 1-7.
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