Monitoring your blood glucose is a key part of managing diabetes. Whether you’re newly diagnosed or have been living with diabetes for some time, understanding your glucose levels can help you feel better day-to-day and reduce the risk of long-term complications.
Blood glucose levels can fluctuate throughout the day depending on what you eat, your activity levels, stress, illness, and medication. Regular monitoring allows you to:
There are several ways to monitor glucose levels. Your diabetes care team can help you decide which options are best for you and how often you should check.
This is the most common method of checking glucose at home. Using a lancing device, you prick your finger to get a small drop of blood, which you apply to a test strip inserted in a glucose meter. The result is usually displayed on the meter in seconds. Always wash and dry your hands before testing for accurate results.
CGMs use a small sensor inserted just under the skin (usually on the arm or abdomen) to measure glucose levels in the fluid between cells. The device sends readings to a display device or smartphone app every few minutes. This provides a detailed picture of how your glucose changes over time. CGM can also alert you to highs and lows and reduces the need for finger pricks. CGM is available on the LTI if you have been diagnosed with Type 1 diabetes for more info on CGM access see tech section
This is a blood test usually done every 6 months by your GP or diabetes clinic. It shows your average blood glucose levels over the previous 2 to 3 months. You cannot carry out this test at home. It gives your HCP a long-term picture of glucose control, and the results of this usually indicate the treatment you are prescribed. For most adults with diabetes, an HbA1c below 53 mmol/mol (7%) is recommended, but your target may be different depending on your individual circumstances.
This is a newer way of assessing glucose control if you use a CGM. It refers to the percentage of time your glucose stays within your target range – usually 3.9 to 10 mmol/L. It offers a more detailed understanding of glucose patterns than HbA1c alone. It helps you see the effect of food, exercise, and medication on your levels.
Your diabetes care team will agree glucose targets that are right for you. These may vary depending on age, overall health, and treatment type. Typical targets for adults with diabetes are:
HbA1c target: usually below 53 mmol/mol (7%). Your target might differ if you have frequent hypoglycaemia, are older, or have other health conditions.
Talk to your diabetes team if you’re unsure what your targets should be.
Not everyone with diabetes needs to check their glucose at home. The decision depends on your type of diabetes, your treatment, and your overall care plan.
Hypoglycaemia (“hypo”) happens when blood glucose levels drop below 4 mmol/L. It can happen if you take insulin or certain diabetes tablets. Recognising symptoms early is important to treat it quickly.
Common symptoms:
Treating a hypo:
Important: Always carry hypo treatment with you. If you drive, follow DVLA/HSE guidance on safe driving and glucose monitoring.
Hyperglycaemia (“high”) means blood glucose levels are above your target range. It can happen for several reasons – missing medication, eating more carbohydrate than usual, being unwell, stress, or not getting enough activity.
Common symptoms include:
Occasional highs are common and usually not dangerous. Persistent high readings, however, should be discussed with your healthcare team.
DKA is a serious, potentially life-threatening condition that happens when your body does not have enough insulin and starts breaking down fat for energy. This produces ketones, which can build up to dangerous levels in the blood.
Symptoms of DKA:
DKA is most common in people with Type 1 diabetes but can also occur in Type 2 under certain conditions (such as severe illness or missed insulin doses).
If you suspect DKA, seek urgent medical help immediately by calling 112 or 999.
