- Ketone bodies
- Chemicals that the body makes when there is not enough insulin in the blood and it must break down fat instead of the sugar glucose for energy. The ketone bodies — acetone, acetoacetate, and beta-hydroxybutyrate — are toxic acidic chemicals. They build up in the blood and then spill over into the urine. The body can also rid itself of acetone through the lungs. This gives the breath a fruity odor. The presence of ketone bodies in the blood is termed "ketosis" and in urine is called "ketonuria."
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three substances that are produced by fatty acid and carbohydrate metabolism in the liver, being β-hydroxybutyric acid, acetoacetic acid, and acetone in approximately a 78:20:2 ratio. Acetoacetate is produced from acetyl-CoA; most is enzymatically converted to β-ketobutyrate, but a small amount is spontaneously decarboxylated to acetone. The ketone bodies can be used as fuels by muscle and brain tissue. In starvation and uncontrolled diabetes mellitus, large quantities are produced, causing metabolic acidosis and elevated blood and urine levels of all three ketone bodies.
Medical dictionary. 2011.