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Fasting blood test

A fasting blood test is a blood sample taken from a person who has not eaten for 8 to 12 hours. Usually, the blood sample is taken early in the morning.

Examples of blood tests that may be done after a period of fasting include fasting blood sugar (fasting plasma glucose) and lipid profile (cholesterol and triglycerides).

Current as of: May 1, 2026

Author: WebMD Ignite Staff

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