Which fasting glucose level is indicative of diabetes?

A fasting glucose level of 125 mg/dl or greater is indicative of diabetes. This measurement falls above the threshold established by health guidelines, which classify diabetes based on elevated blood sugar levels. Specifically, the diagnostic criteria for diabetes include fasting glucose levels at or above 126 mg/dl on two separate tests, or a HbA1c level of 6.5% or higher, among other methods.

In contrast, a fasting glucose level less than 100 mg/dl is considered normal. A level between 100 and 125 mg/dl indicates prediabetes, which is a warning sign that increased risk for developing type 2 diabetes exists. Similarly, a range of 140-199 mg/dl falls within the criteria for impaired glucose tolerance rather than diabetes, typically assessed by an oral glucose tolerance test. Thus, the reference point of 125 mg/dl or greater is critical for diagnosing diabetes accurately.