Hello, I am getting conflicting reports on normal "FASTING" blood sugar levels. The ADA says that normal fasting Blood sugar should be 90-130 mg/dl. The Mayo clinic says that anything over 100 mg/dl is considered "prediabetes". What are the actual numbers?

I have not been diagnosed with diabetes but I have had several incidents in the past few months where I get shaky and sweaty and feeling very week. I have been checking my Blood sugar and it is usually below 100, but this morning I checked it after fasting for 12 hours and it was 101. I would appreciate any replies. Thanks.

There are different diagnostic benchmarks being used. And levels have recently been reduced so that T2 diabetics are are diagnosed sooner and start getting treatment before complications start developing.

This is what endocrineweb.com has to say about it:
Fasting Blood Glucose (Blood Sugar) Level:
The "gold standard" for diagnosing diabetes is an elevated blood sugar level after an overnight fast (not eating anything after midnight). A value above 140 mg/dl on at least two occasions typically means a person has diabetes. Normal people have fasting sugar levels that generally run between 70-110 mg/dl.
It sounds like you have hypoglycemia. Feeling weak and shakey is normally because of low blood sugar. You may find that your blood sugar spikes soon after meals. And then it drops very low a few hours afterwards. The best way to test for this is to have a 5 hour Glucose Tolerance Test done.
Cheers,

Mark;)

Thanks Mark for the info! Is hypoglycemia a precurser to diabetes? My father was a diabetic and I'm worried I'm heading for the same fate.

Thanks Mark for the info! Is hypoglycemia a precurser to diabetes? My father was a diabetic and I'm worried I'm heading for the same fate.

dad22:

What you want to watch out for is any slight increases in your fasting glucose levels. The data indicate that those increases in fasting are detectable after your post-prandial responses (and possibly hypoglycemic responses) are already taking place. Have you asked your physician or other specialist for an oral glucose tolerance test (I agree with Mark suggested, he couldn't have given you any better advice). That will probably clear up that question as to whether or not you should be concerned with making changes if you are developing impaired glucose tolerance/type 2 diabetes. I haven't seen a fasting reference range extended as high as 130 mg/dL, even allowing for experimental variance in the measurement. There is one colleague that I know who does not exhibit any signs of insulin resistance, yet his fasting is around 105 mg/dL. When my fasting was at that level, I was on medication (Amaryl in that case) and I certainly had insulin resistance. The norm fasting range for people with "normal" insulin sensitivity is going to be < 95 mg/dL, in almost all cases.