Why the Gallbladder Matters More Than It Seems

Humans have dozens of organs, although the exact count is debated. In many cases, survival is still possible after several of them are removed, with the brain, heart, liver, lungs, and kidneys among the most vital. The gallbladder is often removed without major effects on survival if people adjust their diet, but it would be inaccurate to call it entirely insignificant. New research suggests that losing it may still raise the risk of certain health problems.

More than 1.2 million people in the United States have their gallbladder removed each year, usually because of gallstones. The gallbladder's main job is to store bile made by the liver and release it into the small intestine when needed. Bile is a greenish-yellow fluid that helps break down fats and is composed mostly of water, along with bile salts, cholesterol, pigments such as bilirubin, and fats.

After gallbladder removal, bile flows directly from the liver into the small intestine. Because the body can no longer release bile on demand, some people have more difficulty digesting fatty or high-fiber foods. That can lead to gastrointestinal changes such as diarrhea, constipation, or gas. Those digestive shifts may affect other parts of the body as well, and gallbladder removal has been associated with conditions ranging from Parkinson's disease to leukemia and heart disease.

Possible health consequences of gallbladder removal

The body is remarkably adaptable and can continue functioning after one or more organs are damaged or removed; even the stomach is not essential for survival. Most people who undergo gallbladder removal do not experience lasting complications, but digestive problems that do arise are grouped under post-cholecystectomy syndrome.

Symptoms of post-cholecystectomy syndrome can include bile-salt-induced diarrhea, bile leakage, blockages, and issues with the valve that regulates the flow of digestive juices between the liver, gallbladder, and pancreas. Up to 30% of people who have had their gallbladder removed develop symptoms of this syndrome, while severe cases appear to affect about 2%. Around three-quarters of patients experience good long-term relief, but ongoing discomfort can remain for the rest.

Short-term risks of gallbladder removal, including the small chance of surgical complications, are fairly well understood. Researchers are still studying possible long-term effects, especially for younger patients who may live many decades after the procedure. Evidence is beginning to suggest that digestive changes after surgery may raise the risk of gastrointestinal cancers and overall cancer risk. In one 2022 study, researchers reported a 19% higher overall cancer risk among people who had their gallbladder removed, with the largest increases seen in leukemia and gastrointestinal cancers such as colon, liver, pancreas, and biliary tract cancer.

Why gallbladder removal may be linked to heart disease and neurodegenerative conditions

Researchers continue to find evidence that gut health affects many other aspects of health. That idea makes sense, since the digestive tract absorbs nearly every molecule that makes up the body's cells. Any condition that changes how nutrients are absorbed or disrupts the gut microbiota, the balance of bacteria in the digestive system, can influence other organs. Ongoing symptoms such as constipation or diarrhea after gallbladder removal may therefore play a role in the development of other conditions.

Gallbladder removal has also been connected to neurodegenerative diseases such as Parkinson's disease. One theory is that the link involves changes in gut bacteria and increased inflammation in the intestines and throughout the body, which may contribute to changes in the brain. Altered bile metabolism may also help explain a possible connection to heart disease, possibly by affecting fat and sugar regulation. In one 2021 study based on South Korean public insurance data, researchers found evidence of a higher risk of heart attacks among the youngest group they studied, ages 40 to 49.

Even now, the human body is not fully understood. Other organs once dismissed as unimportant now have evidence supporting a role in health. Most people can live full lives without a gallbladder, but that does not mean the organ plays no meaningful part in supporting human health.