The debate about the normal blood glucose level for people with type 2 diabetes is one of the most common.

In this article I’ll focus only in individuals with type 2 diabetes, since type 1 diabetes and gestational diabetes have other specifications regarding blood glucose targets and management.

Different types of food such as fruits, milk and starchy foods are all break down into glucose in our bodies which is the body preferable source to produce energy.

Blood glucose level in different places

Blood glucose (commonly called “blood sugar”) level is the amount of glucose that exists in the blood. The blood glucose level is quickly determined by doing a finger prick and using a glucose meter.

This is the most common test done by people with diabetes but there are other ways such as normal blood test (blood sample taken from the arm) and CGM (continuous glucose monitoring).

Different countries use different units to measure the blood glucose levels. In the UK and Canada is used the mmol/L. In the USA and Europe is used mg/dl.

You can convert Canadian or British glucose levels to European or American numbers if you multiply them by 18.

This article will be described using the UK units (mmol/L).

Blood glucose should be checked at different times of the day when you want to have a wider understanding of the diabetes management. By doing it, you can also plan the possible changes to be put in place towards its improvement.

When to check the blood glucose

First of all, it’s important to understand how many times you are willing or should check the blood glucose.

The decision should be based on multiple factors:

  • Types of medication you are taking in
  • If you are on insulin
  • Which insulin regimen
  • Tablets regimen
  • Your routines/lifestyle

Blood glucose levels are the best way to understand how your diabetes is controlled. Doing regular blood glucose tests will help you to understand:

  • Blood glucose levels trends
  • Unexpected rises of the blood glucose levels
  • Decrease of blood glucose levels
  • Confirmation of hypos
  • The way different types of food can impact on the blood glucose levels
  • How physical activity impact on the blood glucose levels
  • How changes in your diet can impact blood glucose levels
  • Understand if diabetes medication is adequate for your needs

As you can see there are plenty of reasons for you to check your blood glucose regularly. By doing so, you are more likely to get your diabetes under control and understand the needs to modify your lifestyle, medication, etc.

The blood glucose levels you should aim for

After understanding why you should check your blood glucose it is important to know which blood glucose levels you should aim for.

As discussed in the article about specific HbA1c targets for each person, blood glucose targets are no exception.  I encourage you to have a discussion with your diabetes team and set the blood glucose targets.

Here is the normal range for blood glucose readings.

TimeTargets (mmol/L)
Before Meals4-7 mmol/L
2h after meals< 8.5 mmol/L
Before bed timeIndividual target (< 10 mmol/L)

In order to improve your blood glucose you should start to focus on the blood glucose in the morning.

Some valuable changes from analysing blood glucose

The blood glucose test in the morning is normally the more accurate because it is done right after a big fasting period.

Also, when you start the day with a lower blood glucose you become more likely to keep the day with a low blood glucose.

To do so, you should think about:

  • The evening meals you eat
    • How can you improve them?
    • Should you reduce portions?
    • Should you replace any ingredient?
  • Bedtime snack
    • What is it?
    • Should you have less?
    • Should you avoid it and have a better food choice at dinner time so you don’t feel hungry before bed?
  • Medications
    • Insulin doses?
    • Tablets?

This rationale will work for any other time also. For example, your blood glucose at lunch time is high. This makes you think about the breakfast time, the medication or insulin at breakfast time and possible changes to be done.

The same for dinner time or for the moment after all meals which will give you a better understanding of what to improve on that specific meals.

Glucose tests after meals

Glucose tests 2h after meals are a great way to understand if the insulin doses are correct or need adjustment (in case you inject insulin at meal times). It is also great to understand the way your meals impact on the blood glucose. 

If your blood glucose 2h after meals spikes +3-4mmol/L from the blood glucose before meal, it can mean that the meal you got was possible too rich in carbohydrates with high glycaemic index.

Regarding the bedtime target, I consider this a very unique target that should be decided by you because everyone have their own experiences with hypers and hypos. So this target should be a decision based on your individual needs.

Of course that should be within a considered “acceptable” range because if blood glucose before bed are too high, the blood glucose in the morning can possibly be affected as well.

This article shows you all the reasons and tools to keep you motivated to check your blood glucose and improve you diabetes management and outcomes.

Be in control of diabetes; don’t let diabetes gets in control.