The duodenum
Duodenum · duodenum
The first short section of the small intestine, where bile and pancreatic juices join your food.
What it does
The duodenum is a C-shaped tube about 25 centimetres long that curves around the head of the pancreas. Ducts from the liver, gallbladder and pancreas empty into it, adding bile to break up fats and enzymes to digest proteins, fats and carbohydrates, and neutralising stomach acid.
Surprising fact
Its name comes from a Latin phrase meaning "twelve fingers' breadth", the length medieval anatomists measured it to be.
Why it matters
Most peptic ulcers actually occur in the duodenum rather than the stomach, often caused by the same bacteria.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.