Back to Ask the Diabetes Team Ask the Diabetes Team

From Denver, Colorado, USA:

With all the questions about the differences between whole blood glucose values and plasma values, why is it so difficult to get a chart with normal plasma values? Whenever someone asks about the subject, they seem to be given a conversion formula and not a chart with a range like I've always had with whole blood readings.


Plasma glucose is about 15% higher than whole blood glucose. Labs have used plasma glucose for a long time: decades.

Meters used to use whole blood glucose; but now, every new meter introduced in the past 3-4 years is calibrated to plasma glucose. That way, the numbers are more like the lab. It's not perfect though. Remember your meter costs only a few dollars, not thousands of dollars like lab instruments.

Why are there no charts: beats me! One might argue, just use the old chart; the blood glucose control will be better. Actually I do tell my patients about the low end of the spectrum, the 50s and 60s, and then let them be a bit lower in the high range.


Original posting 3 Jul 2000
Posted to Blood Tests and Insulin Injections


  Back to Ask the Diabetes Team Return to the Top of This Page

Last Updated: (none)
This Internet site provides information of a general nature and is designed for educational purposes only. If you have any concerns about your own health or the health of your child, you should always consult with a physician or other health care professional.

This site is published by T-1 Today, Inc. (d/b/a Children with Diabetes), a 501c3 not-for-profit organization, which is responsible for its contents. Our mission is to provide education and support to families living with type 1 diabetes.
By using this site, you agree to our Terms of Use, Legal Notice, and Privacy Policy.
© Children with Diabetes, Inc. 1995-2018. Comments and Feedback.