Why does your external sphincter muscle go into spasm after eating?

The external sphincter muscle may go into spasm after eating due to increased pressure in the rectal area from the distension of the bowel as food is digested. This can trigger a reflex response, leading to spasms as the body attempts to maintain control over bowel movements. Additionally, stress or anxiety related to eating or digestive discomfort can also contribute to muscle tension and spasms in the external sphincter.