Ketones are a chemical compound produced by the body to provide energy from the breaking down of fats and protein.

The production of ketones is usually a natural process but people that require insulin doses, such as those with type 1 diabetes, need to be aware that high levels of ketones can quickly lead to a very dangerous condition called ketoacidosis.

Who should test for ketones?

People who should test for ketones are people that make very little of their own insulin. This commonly includes individuals with:

  • Type 1 diabetes
  • LADA diabetes who are on insulin
  • Type 2 diabetes who have decreased beta cell function, or
  • people who have had a pancreatectomy (surgical removal of the pancreas)

Why are ketone levels important?

Ketone levels rise when cells in the body need energy but there is not enough insulin in the body to let glucose from the blood into those cells. As a result the body turns to metabolizing fats and proteins to form ketones to use as energy.

If the body needs to convert energy in this way for an extended period of time, it can cause higher levels of acidic ketones to develop in the blood and have a toxic effect on the body, resulting in a dangerous condition called diabetic ketoacidosis (DKA).

People that don’t make enough of their own insulin need to be aware of any instances in which ketones levels are rising too high.

When to test?

It is advisable to test for ketones in the following situations:

  • If your blood glucose levels are 240 mg/dL or more
  • If you develop higher sugar levels when ill
  • If you are vomiting or experiencing diarrhea
  • During pregnancy

How to test

Ketone tests can be carried either using urine ketone testing strips or using a specialist blood glucose meter that takes blood ketone strips as well as blood glucose test strips.

Most urine ketone tests involve:

  • Taking a fresh sample of urine
  • Dipping the test strip into the sample
  • Shaking off any excess urine
  • Allowing the strip to react with the air
  • Comparing the color of the test pad on the strip against the color chart on the side of the tub of strips to get a result

For more detailed guidance, read the information leaflet provided with your ketone strips, including how long to wait before comparing the color of the strip.

What do the results mean?

The following table indicates what the ketone results mean and what action to take.

Result State Action to take
Under 0.6 mmol/l Normal No action to take
0.6 to 1.5 mmol/l Moderately high Test again after 3 to 4 hours –if ketone level has not decreased, call your health team for advice
1.6 to 3.0 mmol/l High Call your health team for advice
Over 3.0 mmol/l Very high Call your health team for advice