What Does High Ketones in Blood Mean?

high ketones in blood
High ketone levels in your blood could mean that you have diabetic ketoacidosis

Ketones are substances produced by your liver when your body doesn’t have enough glucose (blood sugar) to use as an energy source. When your body is low on glucose or insulin, it finds a way to burn fats for energy. The breakdown of these fats turns into ketones that get into your bloodstream.

Causes of high ketones in the blood include:

If you have diabetes, high ketone levels in your blood or urine could mean that you have diabetic ketoacidosis (DKA), which is a complication of diabetes that may be life-threatening. Monitoring ketone levels through a ketones blood test can help you make sure you receive timely treatment.

Healthy people on a ketogenic (keto) diet may also develop high ketone levels. Keto diets promote weight loss by encouraging your body to make ketones to burn off fat. Since this could have long-term effects on heart health, you should ask your doctor before going on this type of diet.

What happens when ketone levels are high?

If you are healthy and don’t have diabetes, high ketone levels may not necessarily cause any problems. 

However, for some people, too many ketones can be poisonous to the body, upsetting your pH and causing swelling around the brain. They also cause potassium levels to plunge, which can be deadly. 

High ketones in people with type I diabetes can lead to DKA, causing symptoms such as:

How can you check for high ketone levels in the blood?

If you have diabetes or symptoms of DKA, your doctor may ask you to monitor your ketone levels at home every 4-6 hours using at-home test kits.

Your doctor may also order a ketone test if:

  • Your blood sugar levels are above 250 mg/dL for 2 days in a row
  • You want to do heavy workouts and are at risk for diabetes complications

When doing a ketones in blood test at your doctor’s office, they will collect a blood sample from a vein in your arm and send it to a lab to check for ketone levels in your blood. Your doctor may also want to check for the presence of ketones in urine, blood sugar levels and HbA1C.

What do ketone test results mean?

Your blood test for ketones may show results such as:

  • Less than 0.6 millimoles per liter (mmol/L)  = normal
  • 0.6-1.0 mmol/L = slightly high
  • 1.0-3.0 mmol/L = moderately high
  • Higher than 3.0 mmol/L = very high

Your urine test for ketones may show results such as:

  • No ketones
  • Trace amounts of ketones (+)
  • Moderate levels of ketones (++)
  • Large amounts of ketones (+++)

If your blood ketone levels are moderately high to very high, you will need to visit the nearest emergency room, where you will be given an insulin shot. 

Until you receive medical help:

  • Keep drinking water to flush out the ketones through urine.
  • Do not walk or exercise
  • Get rest


Type 1 Diabetes (T1D): Symptoms, Causes, Treatments, Vs. Type 2 See Slideshow
Ketones in blood. https://medlineplus.gov/lab-tests/ketones-in-blood/#

What Are Ketones and Their Tests? https://www.webmd.com/diabetes/ketones-and-their-tests