Fasting sugar is a part of routine blood tests that millions go through every year, as a screening test for your sugar metabolism. It is the best warning sign of adult onset diabetes mellitus, a condition that afflicts over 16 million (12 million diagnosed and 4 million undiagnosed but have the disease)
Normal Reference Standard
Historically, normal reference range is 100-120 mg/dl. In other words, if your fasting blood sugar is 121 or higher mg/dl, you are considered a diabetic. This reference standard was based on research focusing on the incidence of diabetic retinopathy. If your fasting blood sugar is between 100-120, you can consider yourself normal.
Latest Health Studies
Studies have shown that when your blood sugar is 120 mgHg or higher, you are not only exposed to the risk for diabetic retinopathy, but you have already been exposed to significant risks of heart disease. In a study published in the American Journal of Cardiology (March 2002(1);89(5):596-9), researchers reported that people with a fasting blood sugar level of 100-125 mg/dl had an adjusted nearly 300% increased risk of having coronary heart disease than people with a level below 79 mg/dl. This information was compiled from a cross-sectional study of nearly 2500 people.
The Cleveland Clinic Foundation now uses a fasting blood sugar of 90 mg/dl or higher as a biomarker of coronary heart disease risk. This is consistent with our anti-aging goal to keep the fasting blood sugar no higher than 90 mg/dl, regardless of age (and systolic pressure no higher than 120 mm Hg, regardless of age). These more stringent reference standards are used for the simple reason that they represent the optimum level in order for the body to attain longevity and health.