Normal Reference Range for Glucose Rates of Change in Nondiabetic Individuals Using Continuous Glucose Monitoring

While reference ranges for glucose levels are well-established, no physiological benchmark exists for glucose rates of change (RoC), despite the association between rapid glycemic fluctuations and adverse health outcomes. We aimed to define normative RoC values by analyzing continuous glucose monitoring (CGM) data from 153 healthy, nondiabetic individuals (Dexcom G6, up to 10 days). We calculated the percentage of time spent exceeding various RoC thresholds over 5-, 15-, 30-, and 60-min intervals, stratifying results by age and time of day. Over 15 min, the median time with RoC exceeding ±2 mg/dL/min was minimal (1.4% rising, 1.0% falling). RoC was slower when measured over longer intervals, faster when rising than falling, faster during daytime hours, and exhibited modest differences across age groups. We propose a RoC of ±2 mg/dL/min over 15 min as a normative reference, analogous to the 70-140 mg/dL glucose range.