Poorly developed muscles, high cholesterol and excessive bilirubin in bile are all factors that cause gallbladder stones, according to eMedicineHealth. WebMD notes that diet, genetics, lack of movement in the gallbladder and weight are other factors that cause gallbladder stones.
WebMD mentions that gallstones form in the gallbladder. There are two types of gallstones: cholesterol and pigment stones. Cholesterol stones are usually yellow or greenish in color, and these comprise 80 percent of gallstone cases. Obesity is one of the largest contributors to the formation of gallstones because the cholesterol can stop the gallbladder from fully emptying. People with diabetes can form gallstones due to triglycerides, which are fats in the blood.
WebMD adds that estrogen is another factor that can increase cholesterol and reduce mobility in the gallbladder. Cholesterol drugs also may increase cholesterol in the gallbladder. Pigment stones are smaller, and they are comprised of bilirubin. Pigment stones are normally found in people with medical conditions, such as cirrhosis or sickle cell anemia.
eMedicineHealth reports that any leftover bile can also cause gallstones to develop. The effects of gallstones may come in the form of infection, swelling or pressure. A person may feel pain in the gallbladder, and the blockage may lead to complications and death if left untreated.