Self-cannibalism is the practice of eating oneself, it is also called autocannibalism, or autosarcophagy. A similar term which is applied differently is autophagy ,that which specifically denotes the normal process of self-degradation by cells.

While almost an exclusive term for this process, autophagy nonetheless has occasionally made its way into more common usage.

A certain amount of said autosarcophagy occurs unwillingly, as the body consumes dead cells from the tongue and cheeks.

Autosarcophagy can be a form of self harm and a symptom of mental illnesses such as personality disorders, psychosis, or drug addiction. Some people will engage in self-cannibalism as an extreme form of body modification, for example ingesting their own blood or skin. Others will drink their own blood, a practice called autovampirism, but sucking blood from wounds is generally not considered cannibalism. Placentophagy may be a form of self-cannibalism.

Forced self-cannibalism as a form of torture or war crime has often been reported. Erzsébet Báthory allegedly forced some of her servants to eat their own flesh in the early 17th century. Incidents were reported in the years following the 1991 Haitian coup d'état. In the 1990s, young people in Sudan were forced to eat their own ears.

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