Bile is a yellow-green liquid produced by the liver and stored in the gallbladder, then released into the duodenum to aid in fat digestion. The main components of bile include cholesterol, bile salts, and the pigment bilirubin. An imbalance in these components can lead to the formation of gallstones, which can be made of various substances. Cholesterol gallstones occur when there is a disproportion between cholesterol and bile salts. Normally, bile salts dissolve cholesterol to maintain its liquid form, but when cholesterol levels in bile rise too high, it surpasses the dissolving capacity of the bile salts, resulting in cholesterol gallstones. A lack of bile salts can also lead to the development of these stones. Pigment gallstones are often linked to chronic bile infections, particularly in some Asian regions where bile duct infections are prevalent. Individuals with blood disorders causing excessive red blood cell breakdown may have increased bilirubin levels in their bile, leading to the formation of bilirubin gallstones.
