Diabetics have a 'fasting' blood glucose level -when no meals were consumed in the previous eight hours- of 126 mg/dL or higher. Individuals with blood glucose levels reaching 200 mg/dL or higher -regardless of when the last meal was consumed- are also considered diabetic, according to Mayo Clinic.
A fasting blood sugar level less than 100 mg/dL is normal; a level from 100 to 125 mg/dL is considered prediabetes, cites to Mayo Clinic.
In managing the condition, the American Diabetes Association suggests pre-meal and post-meal targets of 70 to 130 mg/dl and less than 180 mg/dl.
In monitoring the progress of diabetics, doctors may perform an A1C blood test, which gauges the average blood sugar level over the previous two to three months.
The oral glucose-tolerance test also requires an 8-hour fast. A specific sugary drink is consumed, and blood is drawn 2 hours later. If an individual shows high blood sugar levels on a random test along with increased urination, thirst or weight loss, diabetes is suspected.