Glycosylated Haemoglobin

Your blood is predominantly made up of red blood cells, which contain a substance called haemoglobin that is able to hold and carry oxygen around your body. Normally, approximately 4-8% of this haemoglobin has sugar molecules stuck to it, making it glycosylated haemoglobin. The amount of glycosylated haemoglobin in your blood is directly related to the concentration of blood glucose. This can be measured by taking a blood sample and analysing the red blood cells. The measurement is known as your HbA1c level.

If your blood sugar control is very good, your HbA1c level will be within the normal range of 4-8%. However, if your control isn’t very stable and your blood sugar has been getting very high, the amount of glycosylated haemoglobin in your blood will be much higher than 8%. This test allows the doctors to measure how well you have been maintaining your blood sugar level over a period of approximately 6 weeks before the test. Ideally you should be aiming to keep your HbA1c level below 7.5%, by doing so you can decrease your risk of developing further complications, such as heart disease and diabetic retinopathy.


Sometimes, the doctor may wish to take a urine sample to measure the level of ketones in your urine. Ketones are produced when your body doesn’t have enough insulin and starts to breakdown your fat to produce energy. This condition is called diabetic ketoacidosis. It usually occurs when you are ill or stressed and aren’t maintaining your blood glucose levels well. It is very serious and requires emergency treatment.


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