Gallstones risk factors: who is more likely to get them

What gallstones are

Gallstones are hard, pebble-like pieces of material, usually made of cholesterol or bilirubin, that form in the gallbladder. They range from the size of a grain of sand to a golf ball. Doctors sometimes call them cholelithiasis (NIDDK). The gallbladder is a small, pear-shaped organ below the liver that stores bile, a fluid the liver makes to help digest fat (NIDDK) (MedlinePlus).

Gallstones are very common, affecting 10 to 15 percent of the U.S. population, almost 25 million people. Most do not block anything and cause no pain. These "silent" gallstones usually do not need treatment (NIDDK).

Who is more likely to get gallstones

NIDDK lists these groups as having a higher risk (NIDDK):

• Women. Women are more likely to get gallstones than men. Extra estrogen from pregnancy, hormone replacement therapy or birth control pills may make gallstones more likely.
• Older people. The chance of gallstones goes up as you age.
• People with a family history of gallstones.
• American Indians, who have genes that raise the amount of cholesterol in their bile and have the highest rate of gallstones in the United States.
• Mexican Americans.

MedlinePlus sums it up the same way: gallstones are most common among older adults, women, overweight people, Native Americans and Mexican Americans (MedlinePlus).

Health conditions

You are more likely to get gallstones if you have (NIDDK):

• cirrhosis of the liver
• infections in the bile ducts
• hemolytic anemias, where red blood cells keep breaking down, such as sickle cell anemia
• some intestinal diseases that affect how nutrients are absorbed, such as Crohn's disease
• high triglyceride levels
• low HDL cholesterol
• metabolic syndrome, which can also raise the risk of gallstone complications
• diabetes and insulin resistance

The metabolic syndrome criteria check covers triglycerides, HDL and the other criteria. See also triglycerides and HDL cholesterol.

Weight and diet

You are more likely to get gallstones if you (NIDDK):

• have obesity, especially if you are a woman
• have lost weight fast, for example after weight-loss (metabolic and bariatric) surgery
• have eaten a diet high in calories and refined carbohydrates and low in fiber

People with obesity may have more cholesterol in their bile, and may have large gallbladders that do not work well. When you go a long time without eating or lose weight quickly, the liver releases extra cholesterol into the bile, and the gallbladder may not empty properly. Losing and regaining weight over and over (weight cycling) may also lead to gallstones (NIDDK). The BMI calculator shows where your weight falls.

NIDDK advises staying away from crash diets and losing weight at a slower pace. If you are starting a very low-calorie diet or having weight-loss surgery, talk with your doctor about how to lower your chances of gallstones; a medicine called ursodiol can help prevent them in people who lose weight rapidly this way (NIDDK).

Signs that need care right away

When a gallstone blocks a bile duct, it can cause a gallbladder attack: pain in the upper right belly, sometimes lasting several hours, often after a heavy meal and in the evening or at night (NIDDK). MedlinePlus adds nausea, vomiting, and pain in the back or just under the right arm as possible signs (MedlinePlus).

NIDDK says to see a doctor right away if you have any of these during or after a gallbladder attack (NIDDK):

• pain in your belly lasting several hours
• nausea and vomiting
• fever, even a low one, or chills
• yellow skin or whites of the eyes (jaundice)
• tea-colored urine and light-colored stools

These can be signs of a serious infection or inflammation of the gallbladder, liver or pancreas. Left untreated, blocked bile ducts can be fatal (NIDDK).

Common questions

What is the "4F" or "5F" rule for gallstones?

It is a memory aid some people use for gallstone risk. NIDDK and MedlinePlus do not print it, so we do not use it here. Their own lists are above: being a woman, older age, pregnancy and hormones, obesity, fast weight loss, family history and certain conditions (NIDDK) (MedlinePlus).

Do gallstones always need treatment?

No. If you do not have symptoms, you usually do not need treatment (MedlinePlus). When treatment is needed, the most common one is removing the gallbladder, and you can live without it (MedlinePlus).

Which risk factors can I change?

Sex, age, family history and genes cannot be changed (NIDDK). Weight, how fast you lose weight, and diet can be; NIDDK also says regular physical activity may lower your chances of gallstones (NIDDK).

Also see fatty liver disease, kidney stones risk factors, diverticulitis risk factors and type 2 diabetes risk factors.