Your pancreas sits mostly on the left side of your body, but it actually stretches across both sides. It’s a long, narrow organ tucked behind your stomach and in front of your spine, spanning from right to left across your upper abdomen. In most adults, it measures about 15 to 22 centimeters (roughly 6 to 9 inches) long.
How the Pancreas Sits in Your Body
The pancreas isn’t neatly contained on one side. It has three main sections, each in a slightly different position. The head, which is the widest part, sits on the right side of your abdomen, nestled into the C-shaped curve of your duodenum (the first section of your small intestine, right after your stomach). The body of the pancreas crosses the midline of your abdomen, running horizontally behind the stomach. The tail, which tapers to a thin tip, extends to the left side of your body and ends near your spleen.
If you placed your hand flat across your upper abdomen, just above your belly button, you’d be covering roughly where the pancreas lies. It sits deep, though. The stomach is directly in front of it, and the spine is directly behind it. This deep, tucked-away position is why the pancreas is essentially impossible to feel from outside the body. Even during a medical exam, doctors can rarely feel the pancreas through the abdomen unless something is significantly enlarged.
Organs Surrounding the Pancreas
The pancreas is packed tightly among other organs and major blood vessels. On the right, the head of the pancreas shares space with the duodenum and the bile duct, which carries bile from your liver and gallbladder. On the left, the tail nearly touches the spleen. The stomach sits like a blanket draped over the front of the pancreas, and several of the body’s largest blood vessels run along its edges. This crowded neighborhood is one reason pancreatic problems can produce symptoms that seem to come from other organs.
Where You Feel Pancreatic Pain
Because the pancreas spans the upper abdomen, pain from pancreatic problems typically shows up in the upper belly, often in the center or slightly to the left. The pain frequently radiates straight through to the back, which makes sense given that the pancreas is pressed against the spine. Many people describe it as a deep, boring pain rather than a sharp surface-level ache.
With acute pancreatitis (sudden inflammation of the pancreas), pain in the upper belly often gets worse after eating, and it can spread to the back or shoulders. The area may also feel tender to the touch. Chronic pancreatitis produces a similar pattern: persistent upper belly pain that worsens with meals. This post-meal worsening happens because eating triggers the pancreas to ramp up its digestive enzyme production, which aggravates inflamed tissue.
Pain from pancreatic issues can sometimes be mistaken for stomach problems, gallbladder attacks, or even back pain, precisely because the pancreas is hidden behind other organs. Upper abdominal pain that bores through to the back and gets worse after eating is a pattern worth paying attention to, since it points more specifically toward the pancreas than toward the stomach or gallbladder.
What the Pancreas Does
The pancreas has two separate jobs, which is unusual for a single organ. Most of it, roughly 95%, produces digestive enzymes that flow into the small intestine to break down fats, proteins, and carbohydrates from your food. This is its “exocrine” function, and it’s why the head of the pancreas is positioned right next to the duodenum: the enzymes have a short trip to where they’re needed.
The remaining 5% consists of small clusters of cells scattered throughout the organ that produce hormones, most notably insulin and glucagon, which regulate your blood sugar. These hormones go directly into your bloodstream rather than into the intestine. When this hormone-producing function breaks down, the result is diabetes. When the digestive function fails, you may have trouble absorbing nutrients from food, leading to weight loss, oily stools, and nutritional deficiencies.
Why Its Location Matters
The pancreas’s deep, central position has real consequences for how diseases are detected. Because it’s hidden behind the stomach and surrounded by other organs, pancreatic tumors and chronic inflammation can grow for a long time without producing obvious symptoms. You can’t see or feel swelling the way you might with a more superficial organ. Imaging like CT scans or MRIs is usually needed to get a clear look at the pancreas, since standard physical exams simply can’t reach it.
The location also affects surgery. The head of the pancreas shares blood supply and connections with the duodenum, bile duct, and major blood vessels, making operations in that area complex. Problems in the tail of the pancreas sit near the spleen, which sometimes needs to be removed along with the affected portion of the pancreas. Knowing which part of the pancreas is involved, and therefore which side of the body is affected, helps determine what kind of treatment or surgical approach is needed.