Lily,

Depending on how you look at it, you and your doctor are both right. It seems that a random (non-fasting) blood sugar level needs to be above 200 to be considered indicative of diabetes (conventional medical definition). A fasting blood sugar test then needs to be done to confirm the random test. However, a random blood sugar test result of 166, if it is representative of your non-fasting blood sugar level, is not healthy. To see why I say this, please go to my post titled, "'High-Normal' Blood Sugar Levels and Organ Damage" in my thread titled "Stuff about Diabetes." You might also want to check out my post, "A Diet to Prevent or Deal with Type 2 Diabetes" in that same thread.

Hopefully, you can find a doctor who is of the opinion that "prediabetes" often leads to diabetes and look at your situation accordingly.