Haemoglobin is a protein that carries oxygen in the blood. HbA1c measures the percentage of haemoglobin attached to red blood cells that also have glucose bound to them.

Your doctor will advise how often you need an HbA1c test – usually every three to six months.

If your HbA1c level is too high, you and your doctor can take action to address this, including monitoring your HbA1c level more often. 

HbA1c level guidelines (South African Diabetes Association):

4 – 6% Normal/non-diabetic

< 7% Well-controlled diabetes

7% – 8% Acceptable diabetic control.

> 8% Poor diabetic control: needs attention.


It’s important for everyone to strive to keep blood glucose levels within a healthy range, but it’s especially critical if you have diabetes:

Too low, and normal thinking and functioning are affected, which may lead to a medical emergency.

Too high over a long period, and damage can occur, sometimes over many years, which may lead to serious health complications.

While the complications of diabetes may sound scary, the good news is that you can greatly lower your risk by controlling your condition well. Part of good diabetes management is being able to recognise the signs of low and high blood sugar, and knowing how to take action if they occur.

Low blood sugar symptoms:

Low blood sugar (hypoglycaemia) can happen if your diabetes medication dose is too high, or sometimes if you skip a meal, or if you exercise without checking your blood glucose.

Symptoms of low blood sugar include: confusion, irritability, shaking/trembling, fatigue, palpitations (fast, pounding heartbeat), clammy hands. Left untreated, hypoglycaemia can quickly become serious, even leading to seizures and diabetic coma.

High blood sugar symptoms:

Symptoms include: frequent urination, increased thirst.

Long-term complications of high blood sugar:

  • Cardiovascular disease (can lead to heart attacks, stroke or damaged blood vessels in the limbs)
  • Nerve damage (can cause loss of sensation, or “pins and needles” in hands or feet)
  • Kidney damage (can lead to kidney failure)
  • Eye damage (retinal damage, which can lead to blindness).
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Diabetes South Africa. Testing. June 30, 2020

Link: https://www.diabetessa.org.za/testing/

American Diabetes Association. Diabetes Care. Lifestyle Management. 40(Suppl. 1): S33–S43. 2017.

Link: http://care.diabetesjournals.org/content/diacare/40/Supplement_1/S33.full.pdf

The Heart Foundation. Diabetes. 2022

Link:  https://www.heartfoundation.co.za/diabetes/

Centers for Disease Control and Prevention. World Diabetes Day. 2022

Link:  https://www.cdc.gov/globalhealth/infographics/diabetes/world-diabetes-day.html


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