Justin Delgado is husband to Kacie Doyle-Delgado, diagnosed at age 11. After more than a decade together, he considers himself to be an expert carb counter and Dexcom inserter. He graduated with his Master of Science in Finance from the University of Utah in 2013 and has been working in commercial banking since then. He attended his first Friends for Life conference in 2015 and is looking forward to volunteering with the teens.
October 5, 2000
Blood Tests and Insulin Injections
Question from Sunnyvale, California, USA:
My brother has mental retardation and was diagnosed with diabetes just three months ago. He was using meter "S", but complained about his finger hurting. So we bought meter "F" to test on his arm. The two meters seem to give very different readings at the same time, plus or minus 100 mg/dl�     � [5.6 mmol/L]. Is that normal or am I doing something wrong? What is the difference between plasma-calibrated results and whole blood?
Blood sugar values from whole blood are typically 10-15% lower than plasma values. In addition, blood sugar values between two different meters should not vary significantly — certainly 100 points is far too much variability. Your physician can compare the meters and a sample of blood taken in the office to help sort out which meter is not testing accurately.