Gallstones are caused primarily by an imbalance in the substances that make up bile in the gallbladder. The main causes include:
- Having too much cholesterol in the bile, which can crystallize and form cholesterol gallstones. This type is the most common.
- Having too much bilirubin, a chemical from the breakdown of red blood cells, which can harden into pigmented gallstones.
- When the gallbladder does not empty properly, bile can become concentrated, promoting stone formation.
Factors that increase the risk of gallstones include being female, age over 40, obesity, pregnancy, family history, certain ethnic backgrounds (Native American or Hispanic), rapid weight loss, diabetes, and certain medical conditions affecting red blood cells or the liver. Hormonal factors like taking birth control pills may also contribute to risk. In summary, gallstones result from chemical imbalances in bile and/or impaired gallbladder function, influenced by multiple genetic and lifestyle factors.
