The human liver is the only internal organ capable of complete regeneration, even if seventy-five percent is removed.
Why it is true
The remaining liver cells multiply rapidly to restore the organ's original size and function within a few weeks, a process unique in the human body.
Source: Hepatology
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Related facts
The liver is the only internal organ capable of fully regenerating itself.
The liver is the only human internal organ capable of complete regeneration, being able to recover its original size even after losing up to seventy-five percent of its tissue.
The liver is the only human internal organ capable of completely regenerating itself, even if it loses up to seventy-five percent of its mass.