4 doctors weighed in:

Could you tell me what happens if you have diabetes and eat before a blood test?

4 doctors weighed in
Dr. James Chu
Internal Medicine - Endocrinology
2 doctors agree

In brief: Post-prandial result

Although most blood tests are supposed to be done in the fasting state, the after-meal (or post-prandial) glucose result can be very useful in certain settings.
If you have diabetes and do a blood test after eating, the result can help determine whether you are eating too much carbs or need medication adjustments. American diabetes assn recommends a post-prandial glucose target less than 180 mg/dl.

In brief: Post-prandial result

Although most blood tests are supposed to be done in the fasting state, the after-meal (or post-prandial) glucose result can be very useful in certain settings.
If you have diabetes and do a blood test after eating, the result can help determine whether you are eating too much carbs or need medication adjustments. American diabetes assn recommends a post-prandial glucose target less than 180 mg/dl.
Dr. James Chu
Dr. James Chu
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Dr. Gutti Rao
Internal Medicine - Hospital-based practice

In brief: Depends

Depends what test you want to do.
If you are checking your sugar, it is likely go up. If you are checking you triglycerides, it may go up as well. Other tests should not have any impact after eating.

In brief: Depends

Depends what test you want to do.
If you are checking your sugar, it is likely go up. If you are checking you triglycerides, it may go up as well. Other tests should not have any impact after eating.
Dr. Gutti Rao
Dr. Gutti Rao
Thank
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