Ketone bodies are acids made when your body begins using fat instead of carbohydrates for energy. When there is not enough insulin to get sugar from the blood and into the cells, the body turns to fat for energy. When fat is broken down, ketone bodies are made and can accumulate in the body. High levels of ketones are toxic to the body. The condition is called ketoacidosis.
Ketones are most likely to show up when there is not enough insulin in the body. This can happen if people who have type 1 diabetes don’t take insulin or don’t inject enough to meet higher demands, such as during illness or stress, or when a pump gets clogged or unattached. It can also happen in people with type 2 diabetes who are insulin-deficient if they get sick.
You may have ketone bodies without having ketoacidosis if your diet is very low in carbohydrates or very low in calories and nutrients.
A urine test is the recommended way to test for ketones. However, a blood test can also be used. You can be tested for ketones at your doctor’s office or at home. The urine test is simple to do at home but it is important that you follow the directions carefully. Only certain home meters can test for ketones at home.
You may be given something called a clean-catch kit. These kits contain a cleansing solution and sterile wipes. This is for use prior to collecting the urine sample. Your healthcare provider may also give you a special diet to follow prior to the test. They may also instruct you to not take certain medications that affect the test. Be sure to follow your doctor’s instructions carefully.
The urine test kit will come with test strips that you dip in the urine sample. If the test strip changes color, that indicates that there are ketones present in your urine.
When Should You Test?
Your doctor or healthcare provider will likely help you understand when it’s important to check for ketones, basing recommendations on your health history.
Typically, it is suggested that you test for ketones whenever:
- Your blood glucose number goes over 300.
- Your skin is flushed or loses color.
- You experience vomiting, nausea, or abdominal pain.
- You are sick (illness, infections, and injuries can cause sudden high blood glucose).
- You have very little energy and feel confused.
- You experience dry mouth or are thirstier than usual.
- You have a difficult time breathing.
- Your breath smells “fruity.”
Pregnant women may be told to test each morning before breakfast and/or any time the blood glucose reading goes above 200.
If you experience one or more of these conditions, check your ketone level. Call your doctor if symptoms persist, your ketone levels are above average or high, or you begin having additional problems.
If you are conducting an at-home test and begin noticing ketones, contact your healthcare provider. The presence of ketones, not just their levels, may be important.
A negative test result means that there are no ketones in your urine.
A positive result is usually listed as small, moderate, or large:
- small: <20 mg/dL
- moderate: 30 to 40 mg/dL
- large: >80 mg/dL
You should take immediate action if your test reveals moderate to large ketone numbers.
As part of your diabetes management program, you and your healthcare provider should develop a plan for what to do if your ketone levels are high. However, if you don’t have such a plan, be sure to contact your doctor immediately. High ketone levels can be sign of a potentially dangerous situation. Ketones alter the chemical balance of your blood. If left undiagnosed and untreated, they can poison the body.
Trace amounts of ketones may mean that your body is in the beginning stages of building up stores. In that case, test again in several hours to see if the amount changes. If it goes up, make an appointment to see your doctor.
If your blood glucose is within a safe range and you are losing weight, the presence of ketones may be perfectly normal. However, if you have diabetes, it’s important that you keep a watchful eye on both your ketones and your blood glucose even as you lose weight.
Be sure you keep records of your results. These will help you and your doctor see if your medication, diet, or any other part of your diabetes care plan needs to be adjusted.
Ketones build up in the blood and urine as fats and are broken down for energy when there is not enough insulin present. In high levels, ketones can be very dangerous and even poisonous. This serious condition is known as ketoacidosis and, if left untreated, can lead to diabetic coma or even death. The symptoms of ketoacidosis can be confused with others (such as the flu or a stomach virus), so be sure to talk to your doctor about a plan for when to test for ketones.
The presence of ketones is not always a problem, depending on other factors such as blood glucose levels and weight loss. However, you should always contact your doctor when ketones are present, even in low levels. Your doctor can inform you if any action needs to be taken.
Testing for ketones is an important step in managing your blood glucose levels. It is fairly easy to do at home and should be done any time you experience any warning signs that ketones may be present. Be sure to contact your doctor any time your results come back that ketones are present. Your doctor will be able to instruct you of what treatment is needed.