Why swallowed hot material can cause lasting injury
A hot coal or heated stone does not stop being dangerous when it leaves the mouth. As it passes through the throat, it can transfer heat to the moist lining of the mouth, pharynx, and esophagus—the muscular tube that carries food to the stomach. Unlike the tough outer skin, these delicate tissues have little protection from a hot object in direct contact with them.
The damage can continue after the object is swallowed. Burns trigger inflammation and swelling; severe burns can kill tissue. Swelling near the throat may interfere with breathing, while deeper injury can lead to bleeding or a hole in the esophagus. As a burn heals, scar tissue may narrow the passage, making swallowing difficult. Such complications can be permanent, though the extent of injury depends on the object's temperature, size, and contact with tissue.
A display of endurance can conceal an emergency
The vocal cords sit in the larynx, above the esophagus, so an object that has already been swallowed does not necessarily burn them. But heat can injure the mouth and throat on its way down, and swelling in that region can threaten the airway. A person may therefore appear to have completed a feat while serious injury is developing out of sight.
The distinction matters: swallowing something hot does not invariably destroy the esophagus, but a severe thermal burn can cause lasting damage and can be life-threatening. What looks like a brief demonstration can set off an injury that worsens over hours, as swelling and tissue damage unfold.
