What is the stomach acid made of?
Stomach acid is made mainly of hydrochloric acid, along with potassium chloride and sodium chloride. It is very strong, with a pH of about 1.5 to 3.5.
Special cells in the stomach lining, called parietal cells, produce hydrochloric acid. The acid helps break down food, activates an enzyme called pepsin that digests proteins and kills many harmful bacteria and other germs swallowed with food.
The stomach protects itself from its own acid with a thick layer of mucus and a bicarbonate solution that neutralizes acid near the stomach wall. The lining is also constantly renewed, with cells replaced every few days. If this protection breaks down, painful sores called ulcers can form.
Heartburn
Heartburn happens when stomach acid flows back up into the esophagus, which lacks the stomach's protective lining, causing a burning feeling. Eating large meals, lying down after eating and certain foods can trigger it. Antacids neutralize acid, and other medicines reduce how much acid the stomach makes.
Did You Know?
Many stomach ulcers are caused by a bacterium called Helicobacter pylori. Scientists Barry Marshall and Robin Warren won a Nobel Prize in 2005 for discovering this.
This answer is general information, not medical advice. For a personal health question, talk to a doctor.