Blood Tests

[lo123]

Does anyone know how long you need to fast for blood tests for HBA1C's? I have my blood test in the morning but the last time the secretary told me to fast from 8pm?? What does everyone else do? I always thought it was 12pm. I forgot to ask!!

 

[Copepod]

There's usually no need to fast before blood is taken for HbA1c, as it's an average of a few weeks / months. Are you thinking of a fasting blood sugar?

 

[sofaraway]

for A1c you don't need to fast it can be done any time.

If they are testing for anything else e.g. cholesterol then you will have to fast, usually for 12 hours, but you can drink water.

 

[lo123]

hi - i think i do need to fast as they are testing for my hba1c and other things!!! the usual! Maybe cholesterol too not sure! It's the usual test they do every 3 months. So if it's 12 hours I need to fast then I need to fast from about 8pm.

 

[Northerner]

I have my blood tests tomorrow too, but as far as I'm aware I haven't been told it needs to be 'fasting'. I'm sure that the last time I'd eaten breakfast as usual and then gone for the tests at around 10 am. What would be the effect of eating be on cholesterol etc.? I can see that it shouldn't affect hba1c by any significant amount.

 

[Northerner]

Answering my own question here, from NHS choices website:

Blood cholesterol level

A blood test is often used to check the amount and type of cholesterol in your body. Cholesterol is a fatty substance that builds up in the artery walls and can lead to serious health problems, such as heart disease. There are two types of cholesterol test and, depending on which type you have, you may be asked to fast beforehand.

A test known as the fasting lipoprotein profile may be used to check how much low density lipoprotein (LDL) or 'bad cholesterol' is contained in your blood. Before having this test, you will be asked not to eat for up to 14 hours so that your body has enough time to digest the food in your digestive system, and to clear any fatty particles from your blood.

It is also possible to have a cholesterol test without fasting, but this test can only be used to measure the total amount of cholesterol and the high density lipoprotein (HDL) or 'good cholesterol' in your blood.

 

[Northerner]

Me again! I've just checked and the envelope I was given to take to the people who take the blood has the 'non-fasting' box ticked, so maybe they aren't that interested in my LDL cholesterol. It also explains why they couldn't give me figures for LDL recently when I asked at my GPs, but did have HDL and total cholesterol.

 

[lo123]

sound thanks - every time i went for blood tests i always had to fast. once when i went i had a hypo the night before and i took some lucozade - the nurse refused to do the test! I had to come back fasting! So was just wondering how long everyone else fasts for 🙂

 

[sugarfreerach]

i've never had to fast for a test, personally i think thats quite dangerous especially for type 2's.

 

[kojack]

i've never had to fast for a test, personally i think thats quite dangerous especially for type 2's.

My companion has a test scheduled for next week. It is a fasting test - only water after 9:00pm.
The test is to be done at 09:00 am. A measured volume of Lucozade consumed immediately afterwards and a second test two hours later.
She had pancreatitis a few years ago and has no foods with refined sugars.
Medics do this test about twice a year to check if insulin is being produced in sufficient quantity.

I have the HbA1c test in 3 weeks. Fasting not required.

 

[aymes]

I've never had to fast for an hba1c and can't think of a reason why you'd need to so think it must be for other tests. I've only ever had to fast for a couple of fasting glucose tests when I was first diagnosed.

 

[g-man]

My companion has a test scheduled for next week. It is a fasting test - only water after 9:00pm.
The test is to be done at 09:00 am. A measured volume of Lucozade consumed immediately afterwards and a second test two hours later.
She had pancreatitis a few years ago and has no foods with refined sugars.
Medics do this test about twice a year to check if insulin is being produced in sufficient quantity.

That sounds like a GTT - Glucose Tolerance Test. Usually only done to confirm a diagnosis of diabetes.

To check for insulin production, you'd have a C-peptide test.

G-man

 

[Caroline]

Every time I've had a blood test, I've been told to fast for 12 hours. I was told tea with no milk and no sugar is fine or plain water but nothing else.

How dangerous it is I think depends on how well controlled the diabetes is in the first place. if any one is worried it is a good idea to talk to medical team or doctor before fasting.

 

[Emmal31]

When I went to get my HBA1c test done after an appointment with the dieticians i was told it was a fasting one even though i protested it wasn't she still wouldn't take my blood and I ended up ringing the diabetic nurses and they said no it's not a fasting one! I was so angry had to back again the next day to get it done and guess what it was the same woman and she said the same thing again but this time I said no read the line above it says 'non fasting lipids!'.

 

[kojack]

That sounds like a GTT - Glucose Tolerance Test. Usually only done to confirm a diagnosis of diabetes.

To check for insulin production, you'd have a C-peptide test.

G-man

I sit corrected. It is indeed a glucose tolerance test

 

[Heb]

I think you should fast for 12 hours before the blood test. That is what I do. However, when you get to the hospital, make sure they realsie that you are diabetic as you should be able to go to the front of the queue so that you are not fasting for longer than 12 hours. Heb

 

[diagonall]

HbA1c = no fasting required.