In 1999 The World Health Organization redefined diabetes into the groups on the parent page

The newly accepted criteria are

A level of > 7.0 mmol/l in a single fasting venous sample is now diagnostic   in the presence of symptoms (thirst and frequent urination)

With no symptoms a second reading of >7.0mmol/L confirms the diagnosis

There are two states of PRE-DIABETES - one is new

The older one is called Impaired glucose tolerance - IGT.

The new one is called impaired fasting glucose - IFG. This category has a fasting level of 6.1 to 6.9

It is possible for a person to be positive to one of these and not the other. These two groups are at greater risk of developing overt diabetes and also stroke and cardiac disease

SO....... if the fasting sugar is beyond 5.5 and less than 7.0 a glucose tolerance test (GTT) is required. In this test the glucose level 2 hours after the glucose load will determine the diagnosis

In the GTT the sugar level at the 2 hr proves diabetes if it is 11.1 or greater. If it is between 7.8 and 11.1 then the subject has IGT