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A member asked:
Can you fast too long before a fasting blood test?
A doctor has provided 1 answer
In a way, yes: If you fast for longer than a day or so, it will alter some blood chemistries. Fasting tests are usually set for an overnight fast, or a 12 hour fast. Prolonged fasting is starvation and it affects the body metabolism.
Answered 1/25/2020
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