The importance of ketones in children with diabetes

What are ketones?

Normally, the body breaks down sugar as a source of energy, through a process that requires insulin. If the body does not have enough sugar or insulin, it will break down fat instead to produce ketones, which can also be used for energy.

If ketone levels are high enough, they can make the body more acidic. In patients with diabetes, this can lead to a dangerous condition known as Diabetic Ketoacidosis (DKA). See five signs and symptoms of DKA.

When should I check for ketones?

High ketone levels are usually associated with high blood sugars, so it's a good idea to check for ketones if your child's blood sugar is above 250 mg/dL. However, it is possible to have ketones with normal or even low blood sugars, particularly during times of illness.

"It is also recommended to check your child for ketones if he/she is having abdominal pain, nausea, or vomiting or any other signs of illness, regardless of whether his/her sugar is high or not," says Huay-Lin Lo, M.D., Pediatric Endocrinologist at Children's Health℠ and Assistant Professor of Pediatrics at UT Southwestern.

How do you check for ketones?

There are two ways of measuring ketone levels in the body – in the blood or in the urine.

Checking blood ketones

Blood ketone testing is performed similarly to blood glucose testing. However, instead of using a glucometer and glucose test strip, a ketone meter and ketone test strip are used. Here are how to interpret the results of blood ketone levels:

• 0-0.5 mmol/L: negative/trace ketones

• 0.6-0.9 mmol/L: small ketones

• 1-1.5 mmol/L: moderate ketones

• >1.5 mmol/L: large ketones

Blood ketone testing provides an accurate, real time measurement of the ketone levels in the body.

"Although only more recently available, blood ketone testing offers certain advantages over urine testing, especially with regard to result interpretation," explains Dr. Lo. "Blood ketone test results can be thought of as more 'real time' than urine ketone testing, since the urine you check at any moment might have been made in your body an hour or two ago, and thus might not reflect your body's in-the-moment ketone status as accurately."

Checking urine ketones

To check for ketones in your child's urine:

1. Collect your child's urine in a small container.

2. Dip the urine ketone strip in the urine.

3. Wait about 15 seconds.

4. Match the color of the ketone strip to the guide on the bottle.

When should I do if my child has ketones?

When your child has ketones, they will need to drink lots of fluids and take extra insulin. The type of fluids to drink and amount of insulin to take will depend on your child's blood sugar and ketone level.

For general advice, read our guide to sick day management. For help managing ketones at home, you can also download the Children's Diabetes Advisor App or call your diabetes care team. If your child does not have a blood ketone meter and you're interested in getting one, talk to your care team at your next appointment.

Learn more about our diabetes program

The nationally recognized diabetes program at Children's Health offers around-the-clock care for children with diabetes. Learn how our experts can help diagnose and treat diabetes in children of all ages.