I've been browsing the threads and I'm wondering if (for some people) there's confusion between the "now this minute" Blood glucose test and the Hba1c
so I thought I'd write a little piece on it.
The test your meter does on that tiny drop of blood produced by the finger stabber, tells you how much glucose is circulating in your blood at the moment you stab your finger. It's units are mmol/l ( millimoles per litre). I mole of Glucose molecules weighs 180 grams. Hence a millimole is 0.18g. If you have 4 litres of blood circulating, you have 0.72 of a gram of dissolved glucose circulating for every 1mmol/l that your meter records. The ideal figure for this is 4.7 mmol/l. Therefore ideally you should have about 19 grams of glucose dissolved in your blood.
Hb A1c is determined by taking a syringeful of blood from a vein and finding out what percentage of the red pigment in it is bonded to glucose. So called GlycylatedHaemoglobin. Haemoglobin picks up glucose whilst being caried round in the red blood cells. The amount it picks up is dependent on the concentration of the glucose that's present. It happens in diabetics and non-diabetics just the same. The tie between the haemoglobin and glucose is irreversible. A red cell lives about 100 days, so, since they're being made and destroyed on a constant producion line, checking the level will show a picture of what the average concentration of circulating glucose has been over the previous 100 days. A non-diabetic has an HbA1c of about 4.5%. 94.5% of their haemoglobin is non-glycylated.
I apologise to anyone who knows all this already. I'm not being patronising, but looking at one or two posts here, made it look as if some people had got confused.
I wonder if that's because folks are being discouraged from doing their own tests and depending on DSNs for all tests.
so I thought I'd write a little piece on it.
The test your meter does on that tiny drop of blood produced by the finger stabber, tells you how much glucose is circulating in your blood at the moment you stab your finger. It's units are mmol/l ( millimoles per litre). I mole of Glucose molecules weighs 180 grams. Hence a millimole is 0.18g. If you have 4 litres of blood circulating, you have 0.72 of a gram of dissolved glucose circulating for every 1mmol/l that your meter records. The ideal figure for this is 4.7 mmol/l. Therefore ideally you should have about 19 grams of glucose dissolved in your blood.
Hb A1c is determined by taking a syringeful of blood from a vein and finding out what percentage of the red pigment in it is bonded to glucose. So called GlycylatedHaemoglobin. Haemoglobin picks up glucose whilst being caried round in the red blood cells. The amount it picks up is dependent on the concentration of the glucose that's present. It happens in diabetics and non-diabetics just the same. The tie between the haemoglobin and glucose is irreversible. A red cell lives about 100 days, so, since they're being made and destroyed on a constant producion line, checking the level will show a picture of what the average concentration of circulating glucose has been over the previous 100 days. A non-diabetic has an HbA1c of about 4.5%. 94.5% of their haemoglobin is non-glycylated.
I apologise to anyone who knows all this already. I'm not being patronising, but looking at one or two posts here, made it look as if some people had got confused.
I wonder if that's because folks are being discouraged from doing their own tests and depending on DSNs for all tests.
