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Fasting plasma glucose test

Fasting plasma glucose test

Overview

The fasting plasma glucose test is the simplest and fastest way to measure blood glucose and diagnose diabetes. Fasting means that you have had nothing to eat or drink (except water) for 8 to 12 hours before the test. You are diagnosed with diabetes if your blood glucose level is 126 mg/dl or greater on two separate tests.

Review Date 2/10/2023

Updated by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.