The stomach

The stomach is a stretchy, muscular bag which stores food and helps to break it down (digestion). Stomach cancer can sometimes spread to the lymph nodes close to the stomach.

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About the stomach

The stomach is a stretchy, muscular bag that stores food and helps break it down through digestion. It is in the upper left-hand side of the tummy area (abdomen).

The upper part of the stomach joins to the oesophagus. The oesophagus is a muscular tube that connects the mouth to the stomach. The lower part of the stomach joins to the first part of the small bowel (the duodenum). The pancreas, gallbladder and liver are close to the stomach. They produce juices and enzymes (chemicals) that help digest food.

After you have chewed and swallowed your food, it passes down the oesophagus to the stomach. The stomach churns up food and mixes it with acid and enzymes. This breaks the food down into much smaller pieces. This is how our bodies get the nutrients needed to give us energy and keep us healthy.

The stomach muscles squeeze together (contract) so that semi-solid food passes from the stomach into the small bowel. Digestive juices from the stomach and pancreas help the small bowel take in important substances from food. These include vitamin B12, iron and calcium.

The position of the stomach

The oesophagus passes behind the liver and joins the mouth to the stomach, just below the chest. Below the stomach is the small bowel.
Image: The illustration shows the stomach and surrounding organs. The oesophagus passes behind the liver and joins the mouth to the stomach, just below the chest. The place where it joins is called the gastro-oesophageal junction. Below the stomach is the small bowel. Also shown is the liver, which sits on the right-hand side of the tummy. The pancreas sits below and behind the stomach. Just above the pancreas and lower end of the stomach is the gall bladder.

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The stomach wall

The wall of the stomach has 4 layers:

  1. The mucosa is the inner layer. It may be called the stomach lining. It contains glands that produce enzymes and acid to help digest food.
  2. The submucosa attaches the mucosa to the muscularis.
  3. The muscularis is a layer of muscle. It squeezes the stomach walls together to help break up the food and move partly digested food into the small bowel.
  4. The serosa is a strong outer layer that covers the stomach.

The stomach wall

An enlarged cross-section of the stomach shows the 4 layers of the stomach wall. These layers are called the mucosa, the submucosa, the muscularis and the serosa.
Image: The illustration shows the gullet (oesophagus) coming down into the stomach. The small intestine runs from the bottom of the stomach to the bottom of the illustration. On the right of the illustration is an enlarged cross section of the stomach wall. This shows the 4 layers of the stomach wall. The mucosa is to the left, on the inside of the stomach. This is shown as a ridged layer made up of small egg-shaped glands that produce enzymes. To the right of the mucosa is the submucosa. To the right of this is the muscle layer. Furthest to the right is the outer layer called the serosa. The 3 outer layers are shown in different colours and textures.

How the stomach works

After you have chewed and swallowed your food, it passes down the oesophagus to the stomach. The stomach churns up food and mixes it with acid and enzymes. This breaks the food down into much smaller pieces. This is how our bodies get the nutrients needed to give us energy and keep us healthy.

The stomach muscles squeeze together (contract) so that semi-solid food passes from the stomach into the small bowel. Digestive juices from the stomach and pancreas help the small bowel take in important substances from food. These include vitamin B12, iron and calcium.

Related pages

Date reviewed

Reviewed: 31 December 2019
|
Next review: 30 June 2022

This content is currently being reviewed. New information will be coming soon.

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