Ketone bodies

Ketone bodies are three water-soluble molecules—β-hydroxybutyrate, acetoacetate, and acetone—produced in hepatocyte mitochondria from acetyl-CoA derived from fatty acid β-oxidation when carbohydrate availability is low. Beyond serving as efficient ATP fuel for brain and heart, β-hydroxybutyrate is an endogenous signaling molecule that inhibits class I histone deacetylases, dampens NLRP3 inflammasome activity, and may improve mitochondrial efficiency, mechanisms relevant to fasting biology and longevity research.