A fasting blood glucose level greater than what value is an indicator of type 2 diabetes?

The diagnosis of type 2 diabetes mellitus is established through several criteria, one of which is the fasting plasma glucose (FPG) level. According to major international guidelines, including those from the American Diabetes Association (ADA) and the World Health Organization (WHO), a fasting plasma glucose level of 7.0 mmol/L (equivalent to 126 mg/dL) or higher on at least two separate occasions indicates diabetes. Fasting is defined as no caloric intake for at least 8 hours. This threshold was established based on data showing a significant increase in the risk of microvascular complications, particularly retinopathy, at this level of hyperglycemia.

A. 5 mmol/L: This value is within the normal range for fasting plasma glucose, which is generally considered to be less than 5.6 mmol/L (100 mg/dL).
B. 6 mmol/L: This value falls within the range for impaired fasting glucose (IFG) or prediabetes, typically defined as 5.6 to 6.9 mmol/L (100 to 125 mg/dL).
D. 8 mmol/L: While a fasting glucose of 8 mmol/L is diagnostic for diabetes, it is not the minimum threshold value used for diagnosis.
E. 9 mmol/L: This value is significantly above the diagnostic cutoff and clearly indicates diabetes, but it is not the threshold itself.

1. American Diabetes Association. (2023). 2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes—2023. Diabetes Care

46(Supplement1)

S19–S40. https://doi.org/10.2337/dc23-S002 (See Table 2.2

"Criteria for the diagnosis of diabetes").

2. World Health Organization & International Diabetes Federation. (2006). Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia: report of a WHO/IDF consultation. World Health Organization. (See Section 3.1

"Recommendations"

Page 9).

3. Johns Hopkins Medicine. (n.d.). Diagnosis of Diabetes. Retrieved from the Johns Hopkins University website. (This resource states: "A fasting blood sugar level of 126 mg/dL (7.0 mmol/L) or higher on 2 separate tests means you have diabetes.").