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To Fast For Hba1c Or Not?

CarlyB

CarlyB

Well-Known Member
Messages
97
Location
Watford, UK
Type of diabetes
Type 1
Treatment type
Insulin
Dislikes
Tomatoes, snobby behaviour
Hi all,

I need to get my HbA1c blood test done this week but can't remember if I have to fast or not?

Please help me clarify this.

TIA
 
Glycated hemoglobin is a form of hemoglobin that is measured primarily to identify the three-month average plasma glucose concentration. The test is limited to a three-month average because the lifespan of a red blood cell is four months. Fasting before the blood is taken isn't going to change something that's looking at the last 3 months. So I'm going to say no, however . . . . . . . .

If they're going to do other blood tests like cholesterol and lipids or whatever, they may need a fasting test, best to ask them.
 
If they are including a full lipid breakdown (cholesterol) then you have to fast for 10-12 hours before the test.
 
@DavidGrahamJones @noblehead I also agree.

Plus, it seems increasingly common to need to fast for 12/24 prior to kidney function test, mainly for creatinine.
So, I fast by default now, book bloods for early in morning. It isn't too disrupting for me, but I'm sure it is for some.
 
I didn't for my last review because no one had said to and it was mid day but when I got there I was told I should have so if I where you I would fast any way then you will be right what ever.
 
For my regular blood test which is fairly comprehensive (lipids bone Hba etc) I am told that I don't need to fast ,although I did when I was diagnosed ,it seems that the criteria has changed
CAROL
 
I looked into this a few months back.
Fasting shouldn't alter the results of an HBa1C test .... HBa1c is an indication of glucose levels over 3 months although by the nature of the life cycle of blood cells it must be biased towards the most recent month's levels.

From everything I have found on the net Blood lipid panel results are not altered to any great degree by fasting/non-fasting.
In a fasting test LDL concentration is actually increased by a very tiny ammount, HDL remains much the same and Triglycerides levels are reduced slightly.

Before a non-fasting test eating a meal very heavily loaded with fats in the hours prior to a test could push the Triglycerides up noticeably.
 
Sirmione said:
I looked into this a few months back.
Fasting shouldn't alter the results of an HBa1C test .... HBa1c is an indication of glucose levels over 3 months although by the nature of the life cycle of blood cells it must be biased towards the most recent month's levels.

From everything I have found on the net Blood lipid panel results are not altered to any great degree by fasting/non-fasting.
In a fasting test LDL concentration is actually increased by a very tiny ammount, HDL remains much the same and Triglycerides levels are reduced slightly.

Before a non-fasting test eating a meal very heavily loaded with fats in the hours prior to a test could push the Triglycerides up noticeably.
Click to expand...

As I need to increase my triglycerides maybe I shouldn't fast!
 
CarlyB said:
Hi all,

I need to get my HbA1c blood test done this week but can't remember if I have to fast or not?

Please help me clarify this.

TIA
Click to expand...
It's the average BG for the last three months or so; no need to fast.
 
I dont necessarily believe the old 'specialist' at my GP surgery but she informed me that no diabetic should ever have to fast for any form of test.

I dont fast for HbA1C but do if its more tests that are being done.

My surgery are used to the attitude they get if they give me a late appointment after fasting from approx 7pm the night before.
 
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