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Normal Blood Sugar?



What is a NORMAL blood sugar range, random or fasting ( for someone without diabetes).I know if it is above 126 fasting, you are considered diabetic. What I want to know is what is usually the highest number if you do NOT have diabetes(at anytime of day). What is a non-diabetic persons blood sugar range supposed to be? My Moms was 159 today(random- I ckd it).Whenever I check anyone`s sugar(randomly) it is always below 100. I am type 2 diabetic, My sister and my brother are both type 1. Diabetes has always been on my Dad`s side. I have read that there is something in both parents that cause children to have diabetes. Mom is always trying to blame Dad, for us having diabetes. So there are a couple of questions that I would like you to answer. Thank you


1) First, it is important to realize that diagnoses of diabetes should be based on lab blood glucose measurement rather than fingerstick measurements which are not as accurate. Normal blood glucose levels are the same in children and adults. "Fasting" blood glucose levels are obtained 8 or more hours without any food or drink with calories. Fasting blood glucose levels under 100 mg/dl are considered normal, and fasting blood glucose levels 126 mg/dl or over are consistent with diabetes. Fasting blood glucose levels between 100 - 125 mg/dl are not normal, but are not defined as diabetes. They are termed "impaired fasting glucose".

"Random" blood glucose levels are obtained any time of the day or night, regardless of how recently a person has taken food or drink with calories. Random blood glucose levels 200 mg/dl or above are consistent with diabetes. Glucose can also be tested in a standardized way with an oral glucose tolerance test: after a normal carbohydrate intake for several days and then fasting overnight, the person drinks a standard glucose solution (75 grams of glucose for an adult) at a lab, and then a lab blood glucose test is performed 2 hours later. Two hour blood glucose under 140 mg/dl is considered "normal". Two hour blood glucose 200 mg/dl or above is consistent with diabetes. Two hour blood glucose between 140 - 199 mg/dl is not normal, but is not defined as diabetes. It is termed "impaired glucose tolerance".

People who have blood glucose levels in the "in between" range (not normal, but not diabetes) may or may not ever develop diabetes. People are diagnosed with diabetes only if they meet specific criteria - blood glucose levels are only one part of the criteria.

2) The family risk of diabetes is different for Type 1 diabetes and Type 2 diabetes. About 15% of people newly diagnosed with Type 1 diabetes have a first degree family member with diabetes. If a mother or father has Type 1 diabetes, their children have about a 4%-8% risk of developing Type 1 diabetes.

In contrast, the family risk with Type 2 diabetes is much higher. If a mother or father has Type 2 diabetes, their children have about a 40% risk of developing Type 2 diabetes. If both parents have Type 2 diabetes, their children have up to a 90% risk of developing type 2 diabetes. In addition, being overweight and inactive increases a person's risk of developing Type 2 diabetes.

There is a family risk associated with diabetes - but it varies considerably depending on the type of diabetes and the family members that are affected. An increased risk for one type of diabetes does not increase a person's risk for the other kind of diabetes

Related Resources:

American Diabetes Association

For more information:

Go to the Diabetes health topic, where you can:

Response by:

Nancy J Morwessel, CNP, MSN, CDE Nancy J Morwessel, CNP, MSN, CDE
Pediatric Nurse Practitioner
Diabetes Center
College of Medicine
University of Cincinnati