Two hours after consuming glucose, a value greater than which threshold indicates diabetes?

• A. <140 mg/dL
• B. >200 mg/dL
• C. 140-200 mg/dL
• D. 100-126 mg/dL

Answer: (B)

During an oral glucose tolerance test, the critical measurement is the blood glucose level taken two hours after consuming a standard glucose load. If that 2-hour value is 200 mg/dL (11.1 mmol/L) or higher, it indicates diabetes. This threshold distinguishes normal glucose handling and impaired glucose tolerance (which fall below that level) from diabetes, reflecting an insufficient ability to regulate glucose after a substantial glucose challenge. In context, you’ll also see separate criteria using fasting glucose or HbA1c, but the post-load threshold of 200 mg/dL or more specifically diagnoses diabetes in the OGTT framework.