The human stomach renews its lining every few days to avoid digesting itself.
Why it is true
Gastric acid is strong enough to dissolve metal, so the stomach needs to generate a new layer of protective mucus every three or four days to prevent autodigestion.
Source: Medical Science
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Related facts
The stomach renews its lining every 3 or 4 days.
It takes your body roughly 12 to 24 hours to completely digest a meal.
The human stomach produces a new layer of mucus every two weeks so it does not digest itself.
The human stomach replaces its lining every three to four days.