The high cost of high-normal blood sugar

Normal blood sugar ranges from 60 to 90 milligrams of glucose per 100 milliliters of blood (mg/dl) before a meal.

High-normal blood sugar is defined as 100 to 125 mg/dl (full-blown type 2 diabetes is diagnosed at 126 mg/dl and above).

Without a blood sugar test, it's impossible to know whether your blood sugar falls within a normal range. And because elevated blood sugar typically does its damage silently, it's easy to brush off what few symptoms there are, like fatigue and mood swings.