Most gallstones are formed from excess cholesterol, which hardens into stones that range in size from tiny (the size of a grain of sand) to large (the size of a golf ball). Less frequently, gallstones are made up of bilirubin, a substance in bile, the fluid that helps us digest food. Both types develop in the gallbladder, and most of the time they do not cause any symptoms. When they do—often when they get stuck in the duct between the gallbladder and the small intestine—they can be extremely painful, mimicking the symptoms of a heart attack in some people. Unfortunately, ox bile will not help once gallstones are causing pain, and surgery to remove the gallbladder is often the most effective solution.
Gallstones are common, occurring in 10 percent to 20 percent of adults. Family history plays a part in their development, as do ethnicity and age. Female sex hormones are strongly implicated in the formation of gallstones, with premenopausal women more than twice as likely as men to form them (that risk evens out after menopause). There are, however, strong links between modifiable lifestyle factors and gallstones, so changes in habits can help reduce the risk.
