+**Ketosis** is a metabolic state where the body, in the absence of sufficient [glucose](/wiki/glucose), shifts its primary energy source to [fat](/wiki/fat). The liver then breaks down fat into [ketone bodies](/wiki/ketone_bodies), which serve as fuel for the brain and other tissues.
+## See also
+- [Ketogenic Diet](/wiki/ketogenic_diet)
+- [Fasting](/wiki/fasting)
+- [Metabolic State](/wiki/metabolic_state)