It’s not just because of alcohol. Any substance that damages the liver including viral hepatitis will do the same thing.
Imagine you get a cut on your skin. The cut will eventually heal but it’s not a perfect 100% replica of the original undamaged skin. There’s some scar tissue that forms which is just fibrous proteins that act as a filler in the spaces where there aren’t normal skin cells anymore.
Likewise, the liver gets inflamed and damaged, and the body attempts to heal it, but it’s not a perfect 100% replica of the original undamaged liver. There’s some scar tissue that’s basically just filler and not actual functioning liver cells. If you repeat this cycle over and over by drinking a lot over the span of years, your liver function progressively worsens.
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