Oesophagus

What and where is it?

The oesophagus is the tube that carries food from your mouth to your stomach. You usually don't notice it unless you swallow something too big, hot or cold, or something is wrong with it.

It runs behind the trachea and in front of the spine, then passes through an opening in the diaphragm, the oesophageal hiatus, to reach the stomach. It is part of the digestive system.

What it does

• Moving food and drink from the throat to the stomach by peristalsis.
• Lubrication: glands in its lining secrete mucus that eases the passage of food.
• Preventing reflux: its lower sphincter normally stays closed so stomach contents do not flow back.
• It adds no digestive juices and does not break food down.

How it works

1. 1
   SwallowingThe tongue pushes food into the throat, triggering an involuntary swallowing reflex.
2. 2
   Protecting the airwayThe epiglottis drops to keep food out of the larynx and trachea.
3. 3
   PeristalsisMuscle behind the food contracts and muscle ahead relaxes, moving it towards the stomach; the brain runs this automatically.
4. 4
   Lower sphincterOpens to let food into the stomach, then closes.

Common problems that affect it

Reflux

• GERD is the most common problem: the muscle at the bottom of the oesophagus doesn't close properly, so stomach acid flows back and irritates it. Heartburn, a burning feeling in the chest or throat, is often caused by reflux.
• Barrett's oesophagus: changes in the lining, often caused by long-term GERD.

Movement disorders

• Achalasia: the lower oesophageal muscle doesn't relax as it should.
• Oesophageal spasms: muscle contractions that cause chest pain or trouble swallowing.

Other problems

• Eosinophilic oesophagitis: a rare condition in which white blood cells called eosinophils build up in the oesophagus, causing swelling, pain and trouble swallowing.
• Oesophageal cancer.

According to MedlinePlus, the risk of oesophagus problems is higher with obesity, pregnancy, certain medicines, radiation to the neck or chest, and smoking or second-hand smoke.

Tests used to study it

The inside of the oesophagus is examined with an upper endoscopy:

• EndoscopyProcedure

Keeping it healthy

• MedlinePlus lists obesity, smoking and second-hand smoke among the risk factors for oesophagus problems, so a healthy weight and quitting smoking help.
• According to the CDC, quitting smoking lowers the risk of oesophageal cancer, and the WHO lists oesophageal cancer among the cancers linked to alcohol.
• According to the NHS, spicy, fatty and acidic foods and caffeinated drinks can trigger heartburn in some people.