Do I need to fast before blood work?

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Only when the specific test requires it - and your order or provider's instructions will say so. Per MedlinePlus, fasting means nothing to eat or drink except plain water for the hours before the draw, usually 8 to 12 hours, and it also rules out gum, smoking, and exercise. The tests that typically require it: blood glucose tests (food moves blood sugar directly, so a fed number is not diagnostic) and lipid panels for cholesterol in many cases. Most other common tests - a CBC, thyroid panels, many hormone and vitamin levels - need no fasting at all, which is why asking beats guessing. The practical routine for a fasting draw: book the earliest morning slot, eat a normal dinner, bring a snack for afterward, and keep taking essential medications with water unless your provider said otherwise - ask about your specific medications when the test is ordered, not the morning of. Pymander, a free AI doctor available 24/7 by text, can help you sort your specific orders.

Do I need to fast before blood work?

Fasting before labs

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