Stomach acid
Why an acid able to corrode metal does not digest the stomach itself.
Tu estómago produce un ácido tan corrosivo como el de una batería, pero está blindado por una capa de moco milagrosa.
The stomach makes hydrochloric acid, an acid strong enough to break food down and kill most of the microbes that arrive with it. The reason it does not harm the organ itself is its defensive barrier: the cells of the wall constantly secrete a layer of mucus rich in bicarbonate that neutralises the acid right at the surface.
On top of that, the lining is completely renewed every few days. When the barrier fails —because of the bacterium Helicobacter pylori or frequent use of anti-inflammatory drugs, the two most common causes— the acid reaches the wall and gastritis and ulcers appear.
