Back to Ask the Diabetes Team Ask the Diabetes Team

From San Jose, California, USA:

I just had a three-hour glucose tolerance test and would like to know the diagnostic criteria.


Nowadays, there is a tendency to use fasting blood glucose levels only for the diagnosis of diabetes. The American Diabetes Association criteria are that fasting levels less than 110 mg/dl [6.1 mmol/L] are normal, between 110 and 125 mg/dl [6.1 and 6.9 mmol/L] is considered impaired glucose tolerance, and over 125 mg/dl [6.9 mmol/L] is overt diabetes. The advantage of the impaired glucose tolerance category is that it gives people whose history may be suggestive of type 2 a chance to see if exercise and weight reduction can lead to an improvement. For people under their mid-twenties, it gives an opportunity to confirm variants of Type 1 diabetes without committing to insulin.

The WHO's (World Health Organisation) criteria are that fasting levels greater than 140 mg/dl [7.8 mmol/L] are diagnostic and that two-hour levels between 140 and 199 mg/dl [7.8 and 11.0 mmol/L] indicate impaired glucose tolerance, and the values greater than 200 mg/dl [11.1 mmol/L] are, again diagnostic of diabetes.


Original posting 18 Oct 2000
Posted to Diagnosis and Symptoms


  Back to Ask the Diabetes Team Return to the Top of This Page

Last Updated: Tuesday April 06, 2010 15:09:14
This Internet site provides information of a general nature and is designed for educational purposes only. If you have any concerns about your own health or the health of your child, you should always consult with a physician or other health care professional.

This site is published by T-1 Today, Inc. (d/b/a Children with Diabetes), a 501c3 not-for-profit organization, which is responsible for its contents. Our mission is to provide education and support to families living with type 1 diabetes.
By using this site, you agree to our Terms of Use, Legal Notice, and Privacy Policy.
© Children with Diabetes, Inc. 1995-2018. Comments and Feedback.