2 doctors weighed in:

Why is fasting generally necessary before a chemical analysis could be done on a patient?

2 doctors weighed in
Dr. James Ferguson
Pediatrics

In brief: Target fixed in time

The normal ( and abnormal) values of any test are established by making the collection standards the same.
Your blood sugar or fat content will differ just after a meal with a milkshake than it would after an overnight fast, since the body takes time to process the meal. Some tests are not as affected by this factors, some are, so whether or not fasting is needed depends on the testing

In brief: Target fixed in time

The normal ( and abnormal) values of any test are established by making the collection standards the same.
Your blood sugar or fat content will differ just after a meal with a milkshake than it would after an overnight fast, since the body takes time to process the meal. Some tests are not as affected by this factors, some are, so whether or not fasting is needed depends on the testing
Dr. James Ferguson
Dr. James Ferguson
Thank
Dr. Leon Katz
Bariatrics

In brief: Cross reaction

Certain foods and beverages can contain products that after break down can mimick certain classes of drugs.
This can give you a false positive result and cause problems in interpreting the lab results.

In brief: Cross reaction

Certain foods and beverages can contain products that after break down can mimick certain classes of drugs.
This can give you a false positive result and cause problems in interpreting the lab results.
Dr. Leon Katz
Dr. Leon Katz
Thank
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