Ketone testing is a key part of type 1 diabetes management as it helps to prevent a dangerous short term complication, ketoacidosis, from occurring.
If you have type 1 diabetes, it is recommended that you have ketone testing supplies on your prescription.
Ketone testing may also be useful in people with other types of diabetes that are dependent upon insulin.
Why test for ketones?
Ketones are produced by the body as an alternative source of energy to sugar. The body produces ketones by breaking down fats, this process is known as ketosis
Ketones may be produced as part of weight loss, however, it’s important for people with diabetes on insulin to note that ketones can be produced when the body has insufficient insulin.
When the body has too little insulin, it means that cells of the body cannot take in enough sugar from the blood. To compensate for this, the body will start to break down fat to provide ketones.
However, if a high level of ketones is produced, this can cause the blood to become acidic which can lead to illness and even potential danger to organs if not treated in time.
This state is referred to as diabetic ketoacidosis
Where can I get ketone testing kits and sensors?
The most accurate way of testing for ketones is to use a meter that measures blood ketone levels.
The following blood glucose meters are able to test blood ketone levels in addition to blood glucose levels:
If you take insulin, you should be able to get these prescribed by your GP.
You can also test urine for ketone levels, however, urine ketone testing is not as accurate as blood ketone testing as the levels of ketones in the urine will usually only reflect a level of up to a few hours previously.
When to test for ketones?
People with insulin dependent diabetes should take a ketone test:
- Any time your blood sugar is over 17 mmol/l (300 mg/dl)
- If sugar levels have repeatedly been over 13 mmol/l (230 mg/dl)
- If you are unwell and have any of the symptoms of ketoacidosis
How to do a blood ketone test
A blood ketone test is carried out in a similar way to a blood glucose test
- Put a blood ketone strip into the meter
- Prick your finger using the lancing device
- Allow blood to the ketone strip
- Wait for the result
- Safely discard the test strip
- Discard the lancet into a sharps bin
Note that only a select number of blood glucose meters provide ketone testing functionality.
How to do a urine ketone test
Before testing, check the expiry date on the tub to ensure the strips are good for use. Also check the instructions which will tell you how long you need to wait, after urine is applied to the strip, before checking the colour chart.
The process for ketone testing will then usually follow steps similar to these :
- Remove a strip from the tub, taking care not to touch the spongy end of the strip
- Pass urine over the test area of the strip or, alternatively, collect urine in a container and then dip the test area of the strip into the urine
- Begin timing immediately after applying urine – the strip will begin to change colour
- After a set number of seconds (check the instructions), compare the colour of the test area to the colour chart on the side of the tub of strips
- Disregard any colour changes that might happen after the set number of seconds has passed
What should the ketone test results be?
- Under 0.6 mmol/L – a normal blood ketone value
- 0.6 to 1.5 mmol/L – indicates that more ketones are being produced than normal, test again later to see if the value has lowered
- 1.6 to 3.0 mmol/L – a high level of ketones and could present a risk of ketoacidosis. It is advisable to contact your healthcare team for advice.
- Above 3.0 mmol/L – a dangerous level of ketones which will require immediate medical care.
Ketone testing for weight loss
Some people use ketone testing as a way to test whether their body is breaking down fat. Higher ketone levels indicates a greater likelihood of weight loss
Note, however, that this use of ketone testing is not recommended by the NHS and ketone test strips provided by your GP are not to be used for this purpose.
For people with diabetes on insulin, having high ketone levels should be regarded as potentially dangerous.