Blood glucose readings and interstitial fluid (ISF) glucose readings taken simultaneously won’t always match, and that is to be expected. There is a 5- to 10-minute physiological delay in ISF glucose response to changes in blood glucose.¹  This difference is similar to a train ride in which a “blood glucose car” is toward the front of a long train and an “ISF” car is toward the rear. Both cars will pass the same points along the way, but the “blood glucose car” does so minutes ahead of the “ISF car.”  Glucose readings based on ISF have been proven to reliably reflect glucose levels.  For specific questions on making treatment decisions based on the Sensor glucose reading, the Glucose Trend Arrow, and Glucose Graph, please contact your health care professional..

1. Rebrin K, Sheppard NF Jr, Steil GM. Use of subcutaneous interstitial fluid glucose to estimate blood glucose: revisiting delay and Sensor offset. J Diabetes Sci Technol. 2010;4(5):1087-1098.