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Blood tests

P

piperjon

Newbie
I’ve recently changed GPs and in an unrelated visit, I had bloods taken as part of my consultation.

Unsurprisingly they came back with my HBA1c levels elevated (I’d had Covid for 2 weeks).

When I queried that they had been taken mid morning, after I’d had breakfast, I was told that as HBA1c tests the previous 3 month BG level, there’s no need to have a fasting blood test.

I’d always previously booked a fasting test. Which one is correct?
 
Your GP is correct, you don’t need to fast for a Hba1c, fasting WILL make a difference to a cholesterol test so if you have all your tests together then it makes sense to always fast before tests but you don’t need to for your Hba1c. I always fast for any tests just in case they do a cholesterol test
 
The HbA1c basically measures how much glucose has stuck to your blood cells throughout their life span. Blood cells generally hang around for about 12 weeks so the HbA1c is considered to be a sort of average of the last 12 weeks sugar levels. Your breakfast will have had no impact on the HbA1c results.
 
piperjon said:
I’ve recently changed GPs and in an unrelated visit, I had bloods taken as part of my consultation.

Unsurprisingly they came back with my HBA1c levels elevated (I’d had Covid for 2 weeks).

When I queried that they had been taken mid morning, after I’d had breakfast, I was told that as HBA1c tests the previous 3 month BG level, there’s no need to have a fasting blood test.

I’d always previously booked a fasting test. Which one is correct?
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Both are correct insofar as what they are measuring. Your Hba1c is an average over about three months, though is slightly weighted towards the last few weeks – and if you’ve had Covid it will quite probably have pushed your average up a bit.

A fasting test measures your glucose at one moment in time and basically helps understand how your body is reacting to the insulin you are producing.

An ambulatory glucose profile measures glucose levels over a period of time, typically 24 hours, and helps understand how your body responds to food and activity. This measurement does of course require the subject to test glucose levels several times a day either by fingerpick tests or a glucose monitor.
 
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