Hi Sue,
Test your fasting blood glucose fingerstick the first thing in the AM when you wake up. (I have my glucometer in a drawer near the toilet.)
Testing the first thing in the morning will give you the best readings on which to base a diagnosis of prediabetes or not. If your fingerstick is higher than 99 the first thing when you wake up, this qualifies as prediabetic. If you measure your fingerstick more than 10 minutes after you wake up, your glucose reading will start to rise because that is the effect that waking up has. Rising blood sugar levels help us to feel more awake, and the longer we have been awake, the higher the level will go....until we start to eat or exercise. Then, all bets are off, because what our blood sugar does during eating or exercising depends on our degree of insulin resistance.
Thank you for asking this great question.
And happy birthday coming up!
Kind Regards,
Dr. Carney