Question 1

after an 8 hour fast, my blood test was normal. my urine test showed glucose, but my gp said it was insignificant. could that mean i have diabetes?

Accepted Answer

: Need more information.  What was the plasma glucose value? You could consider getting an A1c test that does not require fasting. With the information you provided it is not feasible to provide a meaningful opinion.
Wish you good health!

Question 2

i have to fast for 12 hours before blood test. can i drink black coffee during those 12 hours?

Accepted Answer

Yes: One cup won't change your results.

Question 3

to fast for 10 hours and get a blood test tomorrow. how can i avoid the hunger pangs?

Accepted Answer

You can't: Forgive my frankness. Be tough. And be thankful that you live in a country where you only have to ask, "How can I avoid hunger pangs?" when you're fasting for a lab test -- rather than from not having enough food to feed yourself or the people you love. Some of the great world faiths encourage folks to go without food for a time to remind them of those who have none. Let this idea strengthen you.

Question 4

blood test at 5-11 and triglyceride level after 16 hour fast is 603.after three days taking fenofibrates and level of trig. is 80 what the problem ?

Accepted Answer

Hypertriglyceridemia: Hi. Hypertriglyceridemia (hi TG) is often accompanied by low HDL. Fenofibrate is a good drug for hi TG and low HDL. Hi TG and low HDL is often seen in diabetes and prediabetes. Do you know if you're diabetic or prediabetic?  If so, that should also be addressed. Your TG response to fenofibrate has been very gratifying. Eat healthily and exercise regularly. Good luck!

Question 5

can i take metamucil if my doctor told me to fast for 12 hours for blood test ?

Accepted Answer

Before the fast : Starts. Metamucil may have sugar in it, or a sugar substitute. You may take metamucil before starting the fasting period, i.E,  12 hours before the test.

Question 6

i've got a glucose blood test tomorrow morning and have to fast 10 hours before and was wondering whether you can drink water?

Accepted Answer

Yes: Water is fine; nobody wants you to be dehydrated just for some blood tests, but they don't want you to take any food or other fluids which may elevate your blood sugar.

Question 7

very good afternoon doctors. i need to take a fasting blood test for glucose and for cholesterol. how many hours should i be on a fast before the blood test? what time the next day, morning or afternoon, is a good time to get the blood test?

Accepted Answer

: Take the test every morning before breakfast. This will give you an average result over time. Eating a late dinner, reading will be higher than eating an early dinner. In a prior question you asked why you had frequent nocturnal urination, yet stated you were not diabetic. High sugar levels and a1c may be the reason for your need to urinate throughout the night.

Question 8

i ate 6 hours before my blood test for glucose, co2 and other things. i didnt know i had to fast, did this affect the numbers? my glucose is too low, my co2 is 21 and some things were hemolyzed. should i re take?

Accepted Answer

: Six hours of fasting is enough. CO2 result does not change with fasting or not but test error can result a low CO2 and the most often cause is too much time lapse between specimen taken and testing. There is no need for a redrawn specimen if the results are not much outside the norms which can affect the management.

Question 9

i had to fast for a blood test at 9:30 am. i told the nurse i accidentally ate a chocolate at 10 pm the night before & she said it's ok. but now i'm thinking that maybe i ate it at 12 am. how could this affect the results? what to do?

Accepted Answer

: Relax. Fasting for at least 8 hours before the test will produce reliable results.

Question 10

for what length of time do you fast during a blood test?

Accepted Answer

Depends on the test: Most blood tests do not need you to fast. Only some do like for diabetes - usually need an overnight fast.

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Doctor answers about:

12 hour fast for blood test

A member asked:

After an 8 hour fast, my blood test was normal. my urine test showed glucose, but my gp said it was insignificant. could that mean i have diabetes?

A member asked:

I have to fast for 12 hours before blood test. can i drink black coffee during those 12 hours?

A member asked:

To fast for 10 hours and get a blood test tomorrow. how can i avoid the hunger pangs?

A member asked:

Blood test at 5-11 and triglyceride level after 16 hour fast is 603.after three days taking fenofibrates and level of trig. is 80 what the problem ?

A member asked:

Can i take metamucil if my doctor told me to fast for 12 hours for blood test ?

A member asked:

I've got a glucose blood test tomorrow morning and have to fast 10 hours before and was wondering whether you can drink water?

A member asked:

Very good afternoon doctors. i need to take a fasting blood test for glucose and for cholesterol. how many hours should i be on a fast before the blood test? what time the next day, morning or afternoon, is a good time to get the blood test?

A member asked:

I ate 6 hours before my blood test for glucose, co2 and other things. i didnt know i had to fast, did this affect the numbers? my glucose is too low, my co2 is 21 and some things were hemolyzed. should i re take?

A member asked:

I had to fast for a blood test at 9:30 am. i told the nurse i accidentally ate a chocolate at 10 pm the night before & she said it's ok. but now i'm thinking that maybe i ate it at 12 am. how could this affect the results? what to do?

A member asked:

For what length of time do you fast during a blood test?

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