What causes high ketone levels?

The human body primarily runs on glucose. When your body is low on glucose, or if you have diabetes and don’t have enough insulin to help your cells absorb the glucose, your body starts breaking down fats for energy. Ketones (chemically known as ketone bodies) are byproducts of the breakdown of fatty acids.

The breakdown of fat for fuel and the creation of ketones is a normal process for everyone. In a person without diabetes, insulin, glucagon, and other hormones prevent ketone levels in the blood from getting too high. However, people with diabetes are at risk for ketone buildup in their blood.

If left untreated, people with type 1 diabetes are at risk for developing a condition called diabetic ketoacidosis (DKA). While rare, it’s possible for people with type 2 diabetes to experience DKA in certain circumstances as well.

Ketosis: Symptoms, signs, and more »

If you have diabetes, you need to be especially aware of the symptoms that having too many ketones in your body can cause. These include:

If you don’t get treatment, the symptoms can progress to:

You should always seek immediate medical attention if your ketone levels are high.

Testing your blood or urine to measure your ketone levels can all be done at home. At-home testing kits are available for both types of tests, although urine testing continues to be more common. Urine tests are available without a prescription at most drugstores, or you can buy them online.

You should test your urine or blood for ketones when any of the following occurs:

  • Your blood sugar is higher than 240 mg/dL.
  • You have symptoms of DKA.
  • You feel sick or nauseated, regardless of your blood sugar reading.

To perform a urine test, you urinate into a clean container and dip the test strip into the urine. For a child who isn’t potty-trained, a parent can usually press the stick to their child’s wet diaper to test for ketones.

Urine testing strips contain special chemicals that change colors when they react with ketones. You can interpret the test results by comparing the test strip to the color chart on the package. When you have ketones present in your urine, it’s called ketonuria.

An at-home meter is available to test for blood ketones. This is performed in a similar way to a finger-stick glucose test. You prick your finger with a needle and place a small drop of blood onto the testing area.

Doctors often recommend that people who’ve just received a diabetes diagnosis test their ketones twice daily.

While individual testing may vary, in general, results for ketone testing are labeled in the following way:

normal/negativeless than 0.6 millimoles per liter (mmol/L)
low to moderate0.6 to 1.5 mmol/L
high1.6 to 3.0 mmol/L
very highgreater than 3.0 mmol/L

Call your doctor if your ketones are low to moderate, and seek emergency medical attention if your ketone levels are high to very high.

Ketones can make your blood acidic. Acidic blood can cause DKA. The most serious effects of DKA include:

This is why it’s important to have a plan of action in the event that your ketone levels become too high.

Alcoholic ketoacidosis »

Treating high ketone levels can immediately help you avoid hospitalization for DKA. Work with your doctor to decide what you need to do to help manage moderate ketone levels. If you’re unable to treat at home or if your levels continue to rise, you’ll need to receive medical treatment. Treatments can include:

Intravenous (IV) fluid replacement

One DKA symptom is increased urination, which can result in fluid loss. Rehydrating with IV fluids can help to dilute the extra glucose in your blood.

Electrolyte replacement

When a person has DKA, their electrolyte levels tend to be low. Examples of electrolytes include potassium, sodium, and chloride. If a person loses too much of these electrolytes, their heart and muscles can’t function as well.


In an emergency situation, people are usually given insulin through an IV to improve their ability to use excess glucose in the blood for energy. This typically involves testing glucose levels on an hourly basis. When your ketones and blood acid level begin to return to normal, IV insulin may no longer be necessary, and you would resume your normal insulin therapy regimen.

DKA can also be caused by an underlying illness, such as an infection or a severe stomach bug that causes vomiting. In these cases, your doctor may prescribe treatments for the underlying illness as well.

Careful management of diabetes is the key to preventing high ketone levels. Do the following to keep your blood sugar levels healthy and ketone production to a minimum:

Check blood sugar levels regularly

Your doctor will recommend how frequently you should check your blood sugar levels, but this is typically four to six times per day. You should check your blood sugar more often in the following cases:

  • Your blood sugar levels are getting higher.
  • You’re having symptoms of high or low blood sugar.
  • You’re sick.

Follow a healthy diet plan

Managing your carbohydrate intake and insulin dosage is vital for managing diabetes. Be sure to talk to your registered dietitian if you need help managing your diet.