beta-Hydroxybutyric acid (also known as beta-hydroxybutyrate, 3-hydroxybutyric acid or 3-hydroxybutyrate) is a ketone body. It is a chiral compound having two enantiomers, -3-hydroxybutyric acid and -3-hydroxybutyric acid. The concentration of beta-hydroxybutyrate, like that of other ketone bodies, is raised in ketosis.