What Are Ketones?
Ketone bodies are acids made when your body begins using fat instead of carbohydrates from your diet for energy. Normally, your body uses glucose for energy. In the event you are not eating enough carbohydrates to maintain a supply of glucose, or if your body cannot properly use blood glucose to fuel itself (because of insulin resistance), your body will begin breaking down stored fats, which will in turn produce ketones.
Ketones are most likely to show up in people with type 1 diabetes, though people with both types are susceptible.
You may have ketone bodies in your blood because of the following situations:
- Your diet is deficient in carbohydrates, which are used by your body for energy.
- You are losing weight—you naturally produce ketones as a result of weight loss.
- Your diabetes is uncontrolled.
- You are pregnant (this is a dangerous situation, as even a moderate amount of ketones may harm the fetus).
- You have fasted for more than 18 hours.
- You have an eating disorder or are unable to eat. Conditions such as anorexia nervosa, alcoholism, and bulimia lead to dangerously poor nutrition.
Are Ketones a Sign of a Problem?
Not always. 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 you keep a watchful eye on both your ketones and your blood glucose even as you lose weight.
Trace amounts of ketones may mean 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.
Moderate to large ketone numbers may mean your diabetes is out of control. Contact your doctor immediately. This could be a sign of a potentially dangerous situation. Ketones alter the chemical balance of your blood, and if left undiagnosed and untreated, can poison the body.
How Do You Test for Ketones?
A blood test is the most accurate method of measuring ketones (especially when a person with diabetes also has other symptoms of illness such as nausea, abdominal pain, or vomiting). However, a urine test is the most commonly used method—though it is less accurate.
Some blood glucose meters can also measure ketone levels. In addition, at-home urine tests are available. Ask your doctor which testing method they would recommend for you.
If you are conducting an at-home test and begin noticing ketones, contact your doctor’s office staff immediately. The presence, not just the level of ketones, may be important.
When Should You Test?
Based on your personal health history, your doctor or nurse will likely help you understand when it’s important you check for ketones. Typically, it is suggested that you test for ketones whenever:
- 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 feel lethargic (i.e., have very little energy)
- you experience dry mouth or are thirstier than usual
- you have a difficult time breathing
- your breath smells “fruity”
Pregnant women should test each morning before breakfast and any time the blood glucose reading goes above 250.
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.
Ketones build up in the blood and urine as fats and are broken down for energy. 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), which is why a blood test may be more definitive than a urine test in determining if your symptoms are the result of ketoacidosis or another condition.