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

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