Question

Why doesnât gastric juice digest the inside of the stomach?

Answer 1

The inside of a stomach is coated with a lining that protects it.
This lining is made up of cells called epithelial cells. They coat the stomach with a mucus that neutralizes the acid.

The mucus contains bi-carbonate (a base), similar to baking soda.
Acid + Base = water and salt
So, that’s why taking tums or swallowing baking soda water helps an upset stomach.

When your stomach is upset, it means there’s too much acid. Taking a tums neutralizes that overproduction eating also helps to absorb the excess acid.