Organic compounds that result when body fat is broken down for energy.
Glucose is usually used by cells for energy. But, when there's no insulin to help it transport out of the blood and into the cells, the body has an "energy crisis" and starts to break down body fat into ketones as an alternative fuel source. This is called ketosis.
High blood glucose levels (over 250 mg/dl) are one sign that the body may have high levels of ketones circulating in the blood. This can progress to a serious complication called diabetic ketoacidosis. Testing the urine is one way to check for ketones.