The pancreas performs two essential jobs: it produces digestive enzymes that break down the food you eat, and it releases hormones that control your blood sugar. Tucked behind your stomach and in front of your spine, this organ is only about six inches long, but it produces roughly 2.5 liters of enzyme-rich fluid every day. Without it, your body couldn’t extract nutrients from food or move sugar from your bloodstream into your cells.
Where the Pancreas Sits
The pancreas is surrounded by your gallbladder, liver, and spleen. Its wider end, called the head, sits on the right side of your body, nestled into the curve of your duodenum, the very first section of your small intestine. Its narrow tail stretches across to the left, reaching toward your spleen. This positioning is not random. The pancreas delivers its digestive fluids directly into the duodenum, right where partially digested food arrives from the stomach.
Breaking Down Food
The bulk of the pancreas is devoted to digestion. Specialized cells produce about 8 ounces of digestive juice at a time, packed with three key enzymes that each target a different type of nutrient.
- Lipase works alongside bile from your liver to break down dietary fat. Without enough lipase, your body can’t absorb fat or the fat-soluble vitamins A, D, E, and K. The result is diarrhea and greasy, oily stools.
- Protease breaks down proteins into smaller pieces your intestines can absorb. It also plays a protective role, helping destroy certain bacteria and yeast that live in your gut. When proteins go undigested, they can trigger allergic reactions in some people.
- Amylase converts starches into simple sugars your body uses for energy. Too little amylase means undigested carbohydrates pass through your system, often causing diarrhea.
These enzymes are released in an inactive form and only switch on once they reach the small intestine. This is a critical safety feature. If they activated inside the pancreas itself, they would start digesting the organ’s own tissue, which is exactly what happens during a bout of acute pancreatitis.
Neutralizing Stomach Acid
Digestion creates a chemical problem. Food leaving your stomach is soaked in hydrochloric acid, and pancreatic enzymes can’t function in that acidic environment. The pancreas solves this by producing a bicarbonate-rich fluid, essentially a biological antacid. Cells lining the pancreatic ducts secrete a solution so concentrated in bicarbonate that it raises the pH inside the duodenum to around 8.0, shifting conditions from acidic to slightly alkaline. This protects the intestinal lining from acid damage and creates the right chemical environment for enzymes to do their work.
Controlling Blood Sugar
Scattered throughout the pancreas are small clusters of hormone-producing cells called islets. Though they make up only about 1 to 2 percent of the organ’s total mass, these clusters are responsible for keeping your blood sugar within a narrow, safe range. They do this with two opposing hormones.
When blood sugar rises after a meal, beta cells in the islets release insulin. Insulin acts like a key, signaling muscle and fat cells to open channels on their surfaces that let glucose flow in from the bloodstream. Once enough glucose has been absorbed and blood sugar returns to its normal range, the pancreas stops releasing insulin. It’s a continuous feedback loop: rising sugar triggers insulin release, falling sugar shuts it off.
When blood sugar drops too low, between meals or during exercise, alpha cells release glucagon. This hormone tells the liver to convert its stored glycogen back into glucose and release it into the blood, bringing levels back up. Insulin and glucagon work in constant opposition, like a thermostat that can both heat and cool.
Fine-Tuning the Hormone Balance
The islets also contain a third type of cell that produces somatostatin, a hormone that acts as a local brake on both insulin and glucagon. Somatostatin doesn’t travel far. It works right there inside the islet, dampening the activity of neighboring cells to prevent either hormone from overshooting. Research published in the American Journal of Physiology has shown that somatostatin and insulin together are both required to properly suppress glucagon when blood sugar is high. This layered system of checks keeps blood sugar remarkably stable in a healthy pancreas, typically between 70 and 100 milligrams per deciliter when you haven’t eaten.
What Happens When the Pancreas Fails
Because the pancreas handles two very different jobs, problems show up in two different ways depending on which function breaks down.
When the enzyme-producing side falters, a condition called exocrine pancreatic insufficiency (EPI), your body can no longer properly digest food. The hallmark signs are weight loss, bloating, gas, and pale or foul-smelling stools that float because of their high fat content. Over time, poor absorption leads to deficiencies in fat-soluble vitamins and minerals. Chronic pancreatitis, cystic fibrosis, and pancreatic surgery are common causes. Doctors typically diagnose EPI by measuring levels of a specific enzyme called elastase in a stool sample. Low levels suggest the pancreas isn’t producing enough digestive enzymes.
When the hormone-producing side fails, the most familiar result is diabetes. In type 1 diabetes, the immune system destroys beta cells, eliminating the body’s ability to make insulin. In type 2 diabetes, the pancreas still produces insulin, but the body’s cells gradually stop responding to it. The pancreas compensates by making more and more insulin until, eventually, even that isn’t enough. Both forms lead to chronically elevated blood sugar, which over years damages blood vessels, nerves, kidneys, and eyes.
Signs Your Pancreas May Need Attention
Pancreatic problems often develop gradually, and early symptoms can look like ordinary digestive complaints. Persistent diarrhea, unexplained weight loss, or oily stools that are difficult to flush are signs that fat digestion may be impaired. Upper abdominal pain that radiates to your back, especially after eating or drinking alcohol, can point to inflammation of the pancreas. Unexpected changes in blood sugar, such as new-onset thirst, frequent urination, or episodes of shakiness and confusion, suggest the hormone-producing side may be struggling.
The pancreas doesn’t get as much attention as the heart or liver, but it quietly supports two of the body’s most fundamental processes: turning food into usable energy and keeping blood sugar stable enough to fuel every cell you have.