Continuous glucose monitoring
Also known as:
CGM, glucose sensor
A wearable sensor that shows glucose patterns day and night. Essential in diabetes, still evolving outside it.
Written and reviewed by Farhan Tahir, MD · Last reviewed
VIDEO LESSON
What it measures
A small sensor measures glucose in the fluid under the skin every few minutes and shows trends on a phone or reader.
In diabetes
International consensus targets more than 70% of readings between 70 and 180 mg/dL (time in range), with less than 4% below 70 mg/dL for most adults. CGM improves control, especially with insulin.
Without diabetes
Over-the-counter sensors are available, but evidence that they improve outcomes in people without diabetes is limited, and normal post-meal spikes can cause unnecessary worry.
Key studies and references
Educational content only, written and reviewed by Farhan Tahir, MD. It does not replace individual medical advice. For sudden chest pain, trouble breathing or stroke symptoms, call 911.
AT A GLANCE
Test type
Blood sugar
Also known as
CGM, glucose sensor
Reviewed by
Farhan Tahir, MD
Questions about your own care?
Dr. Tahir’s team offers consults through Youthful Medicine.
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