Ketone bodies refer to three molecules, acetoacetate (AcAc), 3-hydroxybutyrate (3HB) and acetone. 3HB is formed from the reduction of AcAc in the mitochondria. These two predominant ketone bodies are energy-rich compounds that transport energy from the liver to other body tissues. Acetone is a minor product, generated by spontaneous decarboxylation of AcAc and is responsible for the sweet odor on the breath of individuals with ketoacidosis.