SurgiSense

What is the pancreas?

The pancreas is a soft, flat gland located behind your stomach, in front of your spine. On average, it is about 15 cm long and weighs around 100g.  The word ‘pancreas’ comes from Greek, meaning ‘all flesh’, because of its soft texture.

It helps break down food and keeps your blood sugar levels in balance.

What is the pancreas made of?

The pancreas is made up of two main types of tissue:

• Exocrine tissue
  This makes up most of the pancreas. It contains clusters of cells called acinar cells, which produce digestive enzymes.
• Endocrine tissue
  Scattered throughout the pancreas are tiny clusters of cells called the islets of Langerhans. These cells produce hormones like insulin and glucagon.

The ducts that carry digestive enzymes are lined with ductal cells. These cells produce a bicarbonate-rich fluid, which helps neutralise stomach acid.

^{modified from OpenStax College, CC BY 3.0 via Wikimedia Commons}

The digestive enzymes they produce flow from the acini into these ducts, which join together to form larger ducts, eventually forming the main pancreatic duct that carries the pancreatic juices into the duodenum – the first part of the small intestine.

The hormones produced by the pancreas are released directly into the bloodstream, rather than into the ducts, and travel through the body to reach the organs and tissues where they are needed.

What does the pancreas do?

The pancreas has two main jobs:

• Digestive: 
  It helps with digestion. When we eat, the pancreas releases special enzymes into the small intestine. These enzymes break down proteins, fats and carbohydrates, so your body can absorb the nutrients it needs.

• Hormonal: 
  It produces hormones such as insulin and glucagon, which keep your blood sugar levels steady. This is important because your cells need the right amount of sugar for energy, and too much or too little can make you feel unwell.
  
  The pancreas also produces other hormones, such as ghrelin, somatostatin and pancreatic polypeptide, which help coordinate digestion, control appetite and fine-tune how the digestive system works.
  

The pancreas works behind the scenes every time you eat, making sure your food is digested properly, your blood sugar stays balanced and your appetite and digestive processes are coordinated just right.

Pancreas and digestion

One of the pancreas’s main jobs is to help with digestion, and this process actually starts before you even take a bite.

When food enters the duodenum, it triggers the release of hormones that also tell the pancreas to get to work. 

• Cholecystokinin (CCK) – signals the pancreas to release digestive enzymes.
• Secretin – signals the pancreas to release a bicarbonate-rich fluid.

The pancreas releases digestive enzymes through the main pancreatic duct into the duodenum – the first part of the small bowel. These enzymes mix with the food and start breaking it down further, helping your body absorb the nutrients it needs.

Each enzyme is specialised for a different type of nutrient:

• Amylase helps break down carbohydrates into sugars.
• Lipase breaks down fats
• Proteases break down proteins into amino acids.

As the food is broken down into smaller molecules, these nutrients can pass through the lining of the small intestine and enter the bloodstream, where the body can use them for energy, growth, and repair.

Pancreatic enzymes act like tiny chemical scissors, cutting large food molecules into small pieces that your body can absorb and use.

Pancreas and sugar levels

The pancreas is your body’s main regulator of blood sugar, adjusting hormone levels to match your body’s changing energy needs.

When you eat, carbohydrates are broken down into sugar, or glucose, which your body uses for energy. As food reaches the small intestine, special cells in the gut detect the sugar and send signals to the pancreas to release insulin.

Insulin helps your cells take in sugar for energy or storage.

The pancreas can ‘sense’ how much sugar is in your blood. When sugar rises, it releases insulin, and when sugar falls, it slows down. Insulin also sends a signal to your brain – mainly the hypothalamus – to let you know when you’ve had enough to eat.

When you haven’t eaten for a while or your body has used up the sugar in your blood, your blood sugar starts to drop and the pancreas releases glucagon. Glucagon tells the liver to release stored sugar, and once blood sugar returns to normal, the pancreas stops releasing it. If your liver has no stored sugar, your body can make glucose from proteins and fats, but this takes longer. Until that happens, your blood sugar can stay low, leaving you weak, lightheaded or unusually hungry.

Together, insulin and glucagon act like a thermostat, keeping your blood sugar steady and your energy balanced throughout the day.

Too much sugar over time can make blood vessels stiff, harm nerves, and affect organs like the eyes, kidneys, and heart. If blood sugar is too low, it can stress your body and brain, making you feel tired, weak, or confused. Keeping sugar levels steady helps your body function efficiently, stay energised and feel well throughout the day.