
What happens in my body when i burp?
No one can resist a deep satisfying burp, especially after a big glug of fizzy pop.
Eat and drink

With every mouthful of food or drink, you swallow a couple of millilitres of air – mostly nitrogen and oxygen. Carbonated drinks also add another millilitre or so of carbon dioxide.
Gases separate

The gases separate from the food in your stomach and press against the lower oesophageal sphincter, which holds the top of the stomach closed.
Sphincter opens

Eventually, the pressure forces the sphincter open and the air rushes out. The belching sound is caused by vibrations in the sphincter and oesophagus wall

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