Diabetics have ketones in their urine because they do not produce enough insulin to break down glucose, leading to the use of fat cells for energy. When these fat cells break down, ketones are produced by a process called ketosis, explains WebMD. Ketones are most commonly found in the urine of type 1 diabetics, according to the American Diabetes Association.
Normally, the body metabolizes carbohydrates from food sources to produce energy. If carbohydrates are not available, such as in diabetics, who lack the insulin required to properly use glucose, the body breaks down fat cells instead, producing ketones as a by-product. A high level of ketones is usually a sign of poorly controlled diabetes. Fasting or starvation, prolonged diarrhea or vomiting, and a low-carbohydrate diet can all cause ketosis, explains WebMD. Pregnant women may also test high for ketones, potentially indicating gestational diabetes.
High levels of ketones may induce difficulty breathing, nausea or vomiting, intense thirst, or fruity-smelling breath, notes WebMD. It may also be a sign of a dangerous condition called diabetic ketoacidosis. In extreme cases, coma or death can occur.
Checking for ketones is easy and can be done at home or in a medical office. Blood tests and urine tests are both effective methods, although WebMD states that a laboratory blood test is the most accurate. The American Diabetes Association recommends contacting a doctor immediately if test results show even a moderate amount of ketones.