How does the liver replace old and dying cells?

The liver maintains its function through a process of constant cellular turnover, where cells replace themselves as the need arises. Under normal conditions, this involves the continuous renewal of tissues at the cellular level.1

When the liver experiences significant loss of mass—such as through the surgical removal of a large portion of the organ—it employs a mechanism known as compensatory hypertrophy. In this process, the remaining liver tissue does not regrow the missing lobes themselves; instead, the residual portions enlarge until the organ reaches a mass equivalent to the original, thereby restoring its full function.1

In cases of disease or injury, the liver also possesses the capacity for regeneration. However, if damage is severe and widespread, such as in chronic conditions, the liver may struggle to regenerate effectively. In these instances, healthy tissue can be replaced by fibrous scar tissue, leading to a condition called cirrhosis, where hepatocytes and bile canaliculi regenerate in a disorderly fashion.2