What plasma glucose value at 2 hours after a 75 g oral glucose load defines diabetes?

• A. ≥200 mg/dL
• B. 140-199 mg/dL
• C. ≥300 mg/dL
• D. 100-125 mg/dL

Answer: (A)

Two hours after the 75 g glucose load, the diagnostic threshold for diabetes is a plasma glucose value of 200 mg/dL or higher. This level shows that the body's ability to handle a glucose challenge is significantly impaired, consistent with diabetes. Values 140-199 mg/dL at 2 hours indicate impaired glucose tolerance (prediabetes), while an abnormal fasting value (100-125 mg/dL) points to impaired fasting glucose, not the post-load criterion. So the 200 mg/dL cutoff is the specific point used to define diabetes after an oral glucose tolerance test.