What should I know about high fasting blood glucose levels with diabetes?

Dr. Jack Merendino, MD
Endocrinology Diabetes & Metabolism
One specific pattern of glucose fluctuations needs special consideration: high fasting blood glucose values. It seems perfectly logical for blood sugar levels to rise after eating, but many people are surprised to find that they have higher glucose levels when they get up than they do before other meals of the day, such as dinner. Higher blood sugar levels in the morning mean that you have less insulin action in your body overnight. We often see this in people treated with medications such as the sulfonylureas, which are more effective at promoting insulin release following eating than during prolonged fasting.
In addition, there are two special conditions that may raise fasting glucose levels. The first is called the dawn phenomenon, which results from an increase in certain hormones in the body, especially the stress hormone cortisol, beginning at three or four o'clock in the morning. Cortisol increases insulin resistance, often causing a rise in blood sugar values. The other problem is called the Somogyi effect. This refers to a blood sugar level that rises in the early morning after the person experiences an unrecognized hypoglycemic event during the night. High morning glucose values should prompt some testing at bedtime and then a few tests at 2 or 3 A.M., just to rule out nocturnal hypoglycemia. Clues to nighttime hypoglycemia include fitful sleep, nightmares, or awakening drenched in sweat.
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In general the goal for all of us, including those with diabetes is to try keep our fasting blood sugar stable at 100 or below.

There are two basic tests to measure blood glucose or blood sugar levels.

1.)   The A1C test which reflects your average blood sugar levels over the last 3 months.

2.)   The blood glucose test that you can do yourself at home.

Usually, fasting blood glucose levels of:

100 mg/dl are considered Normal

100-125 mg/dl = pre-diabetic

Over 126 mg/dl = diabetic

Hemaglobin A1C or  A1C numbers that your health provider can measure are usually as follows:

Normal = 6 or less

Pre-Diabetic = 7

Diabetic = more than 7

Additional information on blood sugar numbers can be found here :

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.