High levels of ketones in urine, or ketonuria, is usually a sign of diabetic ketoacidosis (DKA). The body produces ketones when it burns fat for fuel. DKA is a severe complication of diabetes that can cause fatigue and nausea and may damage vital organs.

Untreated DKA can be fatal.

Some people with uncontrolled diabetes may develop DKA with excretion of large amounts of ketones in their urine. People who are fasting or on low carb diets may also eliminate ketones in their urine.

Symptoms of DKA vary in severity. However, they can include ongoing nausea, fatigue, or difficulty breathing.

Continue reading for more information on the causes, various risk factors, symptoms, complications, and ways to treat or prevent ketones in the urine.

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Ketones are most common in people who do not consume enough carbohydrates. The human body uses simple carbohydrates from starchy foods, honey, and certain fruits to produce glucose (blood sugar). Glucose serves as the body’s main source of energy.

When the body does not have enough glucose, or when it does not have sufficient insulin to use the glucose, it begins to use fat for energy instead. This results in the production of ketones.

Ketones are essential to maintaining a healthy body. In fact, both fat and protein consist mainly of ketones.

People with uncontrolled diabetes require insulin to utilize glucose as energy. If the person does not have enough insulin in their body, they will use fats and protein as their energy source.

This process leads to production of ketones and build-up of acid, called DKA. DKA may also occur in the setting of physical trauma, high levels of stress, infection, heart attack, or stroke.

DKA is a potentially life-threatening condition, as well as one of the first signs that a person has diabetes prior to diagnosis. A doctor may test for abnormally high levels of ketones in the urine or blood to check for DKA, as well the first signs that a person has type 1 diabetes.

The most common way to test for ketones is through a urine or a blood test.

People who have type 1 diabetes, low blood sugar, or experience other symptoms related to DKA should consider taking a urine test to detect and measure the level of ketones they have.

There are two ways to administer a urine test.

  • In a medical facility. Prior to the test, the person should not consume anything for several hours. They must then collect between one and two ounces of urine in a sterile container and provide it to a doctor for testing.
  • At home. For at home testing, a doctor may provide the person with a test strip and urine collection container. The test strip and the container will both have a color chart that indicates the ketone level. Again, the person must not consume anything for several hours before the test.

In both cases, the ketones in urine test will determine whether the level of ketones is small, moderate, or high. Various factors such as gender, age, medical history, existing medication, diet, and activity level may influence this number.

Blood test for ketones

Ketones show up in the urine and in the blood. Blood levels of ketones require blood draw, usually in a hospital. People who take insulin shots should monitor their blood glucose at home.

To check blood for ketones, blood draw will be done at a facility, usually in a hospital setting. While there are Over the counter home ketone meters, marketed for keto dieters, these are not standardized. The ADA does not recommend home blood ketone tests, only urine.

This test is done in the hospital or emergency department when DKA is suspected. Other blood tests obtained when DKA is suspected include kidney function, electrolytes, glucose, liver function, pH (or acidity), and blood count.

Evaluating the results

The results from a urine test for ketones will either come back negative or abnormal. A negative test result means the ketone levels are normal for the individual. An abnormal result means the test detected ketones in the urine. This result falls into three categories:

  • Small levels of ketones: Less than 20 mg/dL
  • Moderate levels of ketones: Between 30 and 40 mg/dL
  • Large levels of ketones: Above 80 mg/d, which needs immediate medial attention

As for the blood test, the results fall into three main ranges:

  • 0.6 mmol/L or below. This is the normal range.
  • 0.6 to 1.5 mmol/L. There are ketones in the blood. The doctor will discuss a treatment plan and follow-up.
  • 1.6 mmol/L or above. This indicates a high risk of developing diabetic ketoacidosis. Your doctor will discuss immediate treatment measures.

A urine test only checks for current or recent ketone levels, so a blood test may be more accurate. However, an abnormal or high result could be due to other factors such as:

  • recent illness or high fever
  • low carbohydrate or high protein diet
  • eating disorder such as anorexia
  • excessive alcohol consumption
  • hyperthyroidism (overproduction of the thyroid hormone)
  • breastfeeding

If a person is unsure of their results, they should contact a healthcare professional to interpret the results, especially for at-home testing.

According to the Centers for Disease Control and Prevention, people who have low insulin levels and high blood sugar are most likely to have a buildup of ketones, which develops into diabetic ketoacidosis.

Other reasons why a person may develop ketoacidosis include:

  • type 1 or type 2 diabetes, especially when glucose levels are dangerously high
  • pregnancy
  • substance use disorder
  • prescription medications such as diuretics or corticosteroids
  • pancreatitis or another illness
  • infection that results in higher levels of cortisol, adrenaline, or other hormones that counter insulin
  • prolonged fasting
  • stroke or heart attack
  • trauma
  • missed doses or inadequate amounts of insulin in the body
  • extreme exercise when blood sugar is high and there are high levels of ketones in the body as this can increase blood sugar levels

DKA is a medical emergency that requires immediate medical care. Other health concerns related to high levels of ketones in the urine include hyperglycemia, dehydration, and acidosis.

The most common symptoms of diabetic ketoacidosis or ketones in the urine are:

  • fatigue or exhaustion
  • sudden weight loss
  • sore or aching muscles
  • more frequent urination
  • shortness of breath or labored breathing (dyspnea)
  • excessive thirst
  • nausea or vomiting
  • pain in the abdomen

A few other, less common symptoms associated with this condition include:

People with any of these symptoms or with type 1 diabetes should immediately consult a doctor or conduct a urine or blood test.

Complications of diabetic ketoacidosis may include:

  • cerebral edema
  • hypoglycemia
  • low potassium levels
  • acute kidney failure
  • shock
  • stroke
  • pulmonary edema

These complications may lead to other problems such as a loss of consciousness or even death.

There are several effective ways to treat and prevent high levels of ketones in the urine and the onset of diabetic ketoacidosis. Popular treatments include insulin therapy, fluid replacement treatment, and electrolytes replacement.

People with type 1 diabetes should do the following to prevent ketones from building up in the body:

  • Monitor insulin and blood sugar levels daily.
  • Stay on top of any existing insulin therapy plan.
  • Create a dietary plan that includes carbohydrates to increase glucose levels.
  • Stay hydrated to help flush out the ketones.
  • Get around 150 minutes a week of moderate exercise.
  • Check for ketones in the blood and urine via at-home or in-lab testing.

By taking these steps and establishing and following an insulin therapy or treatment plan, people who are at higher risk of developing DKA can help prevent or manage it.

A person should seek medical attention if they experience any of the following symptoms:

  • frequent vomiting
  • difficulty breathing
  • stomach or abdominal pain
  • unquenchable thirst
  • frequent urination
  • fatigue
  • inexplicably fruity-scented breath

Additionally, it may be wise to speak with a doctor if the results from an at-home blood or urine test come back abnormal. People should seek emergency medical attention if these symptoms persist or get worse.

Ketones in the urine is the result of utilization of fats and proteins as energy source. In uncontrolled diabetes with insulin deficiency, glucose is not used as energy. The rapid production of ketones from fat and protein breakdown may lead to diabetic ketoacidosis.

While having low or moderate amounts of ketones may result in weight loss, high levels can be dangerous or even fatal. This is especially so in people with type 1 diabetes.

Early signs of DKA include fatigue, muscle pain, vomiting, and shortness of breath. Individuals who experience any of these symptoms should seek medical attention immediately or perform a urine or blood test for ketones.