Urine Ketones (KET): What Your Result Means

What are urine ketones

Ketones (KET) are substances produced by the body when it begins using fat for energy instead of glucose. This is a natural metabolic process that occurs when the body does not receive enough carbohydrates or cannot effectively use glucose. Ketones are produced in the liver, and their excess is excreted through urine.

Urine ketone testing is performed with a dipstick — a quick, simple, and non-invasive test often included in a general urinalysis.

Normal ranges

A normal result is negative — there should be no ketones in urine, or their level should be below the detection threshold. Laboratories typically report the result as negative, weakly positive, moderately positive, or strongly positive.

Why urine ketones may be elevated

The most common causes are relatively harmless: prolonged fasting or a very low-carbohydrate diet (ketogenic diet), intense physical exercise, vomiting or diarrhea, especially in children. During pregnancy, ketones may appear due to morning sickness and inadequate nutrition.

However, there are more serious causes. Diabetic ketoacidosis (DKA) is a dangerous complication most commonly seen in type 1 diabetes, when the body lacks insulin and ketones accumulate to dangerous levels. Alcoholic ketoacidosis may occur after prolonged alcohol consumption without adequate food intake.

Why urine ketones may be low

A negative ketone result is the norm. It means the body is receiving enough glucose from food or glycogen stores and does not need to intensively burn fat for energy. This is a good result, especially for people with diabetes.

What to do next

If ketones are detected in your urine and you are following a ketogenic diet or recently fasted for an extended period — this is an expected and usually harmless finding. However, if you have diabetes and ketones are found in your urine, especially along with elevated blood glucose, nausea, or abdominal pain — seek medical attention immediately, as this may be a sign of ketoacidosis.

Your doctor may order blood glucose, HbA1c, and blood gas tests to assess the situation.

Monitoring over time

People with type 1 diabetes are recommended to regularly check urine ketones, especially when ill, when blood sugar is high, or during stress. Ketone test strips are available at pharmacies and can be used at home.

For people without diabetes who follow a ketogenic diet, ketone monitoring can help assess whether the body is in a state of ketosis.

Questions for your doctor

1. Could my ketone levels be related to diet or fasting? 2. Should I check my blood glucose and HbA1c? 3. I have diabetes — could this be a sign of ketoacidosis? 4. How often should I check ketones at home?