Guide

Most liver blood panels don’t require fasting, yet many labs request 8–12 hours when other blood tests are ordered at the same time.

Many lipid panels can be done without fasting, yet fasting 9–12 hours is still used when triglycerides need a cleaner read.

Many liver panels don’t require fasting, but an 8–12 hour fast may be requested when other blood tests are ordered too.

A magnesium blood draw rarely needs fasting; only fast if it’s paired with a fasting panel.

Most Lyme blood tests don’t require fasting, yet fasting can be requested when your draw includes other tests that do.

Many upper-abdomen scans call for 6–12 hours without food so gas stays low and the gallbladder stays full for cleaner images.

No, most prenatal blood draws don’t need fasting, but glucose and lipid tests may require an 8–12 hour fast.

Most people don’t need fasting for a prolactin check; timing, rest, and your medicine list often matter more than breakfast.

A progesterone blood test usually doesn’t require fasting, so you can eat normally unless your lab orders it alongside fasting tests such as glucose or lipids.

Fasting usually isn’t needed before a PSA blood test, so you can eat and drink normally unless your appointment includes other fasting labs.