Urine Ketones (U-KET)

What is Urine Ketones?

Urine ketones are byproducts of fat metabolism that appear when your body breaks down fat for energy instead of using glucose. This test detects acetoacetic acid and other ketone bodies that spill into urine when ketone production exceeds normal levels.

Why is it Tested?

Doctors order urine ketone tests to monitor diabetic patients for ketoacidosis, evaluate people following ketogenic diets, or investigate symptoms like nausea, vomiting, or rapid breathing. It’s especially important for type 1 diabetics who are at higher risk for dangerous ketone buildup.

Normal Ranges

Normal urine ketone levels:

Normal: Negative or less than 5 mg/dL
Small: 5–15 mg/dL
Moderate: 15–40 mg/dL
Large: Greater than 40 mg/dL

Negative results are normal for most people, though small amounts may be normal during fasting or low-carb dieting.

Reference ranges vary by authority. Track yours across multiple standards with automatic unit conversions in LabsVault.

What do Abnormal Results Mean?

Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.

Small to Moderate Ketones (5-40 mg/dL)

Elevated ketones at these levels may indicate:

Ketogenic diet or fasting
Inadequate carbohydrate intake
Mild diabetic ketosis
Illness affecting eating patterns
Intense exercise

Large Ketones (>40 mg/dL)

High ketone levels can signal serious conditions:

Diabetic ketoacidosis (medical emergency)
Severe dehydration or illness
Prolonged starvation
Alcoholic ketoacidosis
Need for immediate medical attention

How to Track Over Time

Monitoring ketones helps diabetic patients prevent life-threatening ketoacidosis. For people on ketogenic diets, tracking shows whether they’re maintaining ketosis. Rising ketone levels in diabetics, especially with symptoms, require urgent medical evaluation.