Esophagus

The 25 cm chute

How does the esophagus work?

A muscular tube that pushes food from throat to stomach in waves (peristalsis) — it works even upside down.

How it moves food

Rings of muscle contract in sequence behind the food; gravity helps but isn't required.

The valve

The lower esophageal sphincter keeps stomach acid out. When it relaxes at the wrong time, acid reflux causes heartburn.

When to get help

Trouble swallowing, food sticking, or frequent heartburn are worth discussing with a clinician.

Evidence & sources

• Gastroesophageal reflux disease (GERD) occurs when stomach contents repeatedly flow back into the esophagus and cause symptoms or complications. Evidence: established. Known: Standard clinical definition. Unknown: — Source: NIH NIDDK, Acid Reflux (GER & GERD) in Adults (Current revision).

Connected topics

• Mouth & Teeth
• Stomach
• Digestive System

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.