Can a person unknowingly have diabetes and an 8 hour fasting blood sugar test not catch it?

If they are actually DIABETIC, then an 8 hour fasting test should catch it.

If they are only pre-diabetic, then an 8 hour fasting test might miss it.

Yes.

Diabetes take 2-5 YEARS to develop to the point it is painful. In most cases, diabetes is found only when the patient needs to be in the hospital, like an emergency.

THAT is why most doctors do the A1C Blood Test to EVERYONE, at least once a years. By taking this test you can find out if you haev diabetes in 3 or 4 MONTHS, not 2 to 5 YEARS. THIS WILL SAVE YOUR LIFE.

Taking one or two tests AT HOME with the little home meter WILL NOT diagnose diabetes. YOU MUST get the A1C test done at your doctors office.

Home sugar blood level tests may vary, and washing your hands before a blood probe won't do, wipe your finger with some isopropylol (or disinfectant tissue, that's the same), wait half a minute, and then take the probe. That's a more reliable result, note it, and repeat three times a day, if you can't do it at a hospital, and EXCATLY note what you have been eating, and how much.

After 8 hours fasting, my sugar level would be down to 60, with a regular 110 to 130. To measure real life sugar levels, you must make people eat the things they usually eat, and if you really have diabetes, closely watch them to adjust the medication.

I remember one doctor once who measured my sugar level which was at 55, she said, I wonder you can walk. I answered, me too, I worked all day and I'm really hungry now.

If all that is being done, is a finger stick to get a fasting reading, and not an a1c, then yes, it is possible to have a random normal finger stick reading. You would not however pass an A1c, if your bg levels have been consistently 160 to 300 most of the day for months.

When I test first thing in the morning my readings are 79 to 110 most mornings. So even with diabetes, a doctor seeing those readings would not think to do an a1c, at least not based on those numbers).

Yes, because your body is still producing some insulin, so a low carb dinner (meat and vegetables, and water) plus some strenuous exercise that day would all help your body get within range for the 8 hr fasting test. That is why the a1c (a 3 month average) is also very important.

no