Blood Sugar Levels Chart: Before and After Eating
A blood sugar levels chart can help you understand the difference between fasting, pre-meal and post-meal readings. But the right target is individual. Your diabetes team may set a range based on your medication, age, pregnancy, health conditions and risk of hypos.
What do blood glucose readings show?
Blood glucose readings show the amount of glucose in your blood at a particular moment. They can change after food, exercise, illness, stress, alcohol and medication.
In the UK, readings are commonly shown in mmol/L.
Typical targets for people with diabetes
A common general guide for many adults with diabetes is:
| Timing | Common general target |
|---|---|
| Before meals | Around 4–7 mmol/L |
| About two hours after meals | Often below 8.5–9 mmol/L |
These are not universal targets. Children, people who are pregnant, people using insulin and people at risk of hypoglycaemia may be given different advice.
Why timing matters
A reading before breakfast tells a different story from a reading two hours after a meal. When logging your result, record the time and whether it was before or after food. That context makes your data much more useful.
When to get advice
Contact your diabetes team or GP if your readings are regularly outside the target you have been given. If you feel unwell or have symptoms of very high or very low blood sugar, follow your care plan and seek urgent advice where appropriate.
Track the pattern in Pulse
Pulse lets you store glucose readings alongside your blood pressure and HbA1c. Create a Pulse account to keep your health data in one place.