Gallstones are hardened formations, composed primarily of cholesterol, that develop in the gallbladder.
Gallstones are commonly associated with bile that contains excessive cholesterol, a deficiency of other substances in bile (bile acids and lecithin), or a combination of these factors.
What are the symptoms of gallstones?
Gallstone attacks cause extreme pain in the upper-right quarter of the abdomen, often extending to the back. This pain can be accompanied by nausea and vomiting.
Dietary changes that may be helpful for gallstones
Cholesterol is the primary ingredient in most gallstones. Some,1 but not all,2 research links dietary cholesterol to the risk of gallstones. Some doctors suggest avoiding eggs, either because of their high cholesterol content or because eggs may be allergenic. (See the discussion about gallstones and allergies below.) A recent study of residents of southern Italy found that a diet rich in sugars and animal fats and poor in vegetable fats and fibers was a significant risk factor for gallstone formation.3
Most studies report that vegetarians are at low risk for gallstones.4 In some trials, vegetarians had only half the gallstone risk compared with meat eaters.5 6 Vegetarians often eat fewer calories and less cholesterol. They also tend to weigh less than meat eaters. All of these differences may reduce gallstone incidence. The specific factors in a vegetarian diet that account for a low risk of gallstone formation remain somewhat unclear and may only be present in certain vegetarian diets and not others. For example, some studies have found that vegetarians eating a high vegetable fat diet had elevated rather than reduced risks of gallstone formation.7 8
Coffee increases bile flow and therefore might reduce the risk of gallstones. In a large study of men, those drinking two to three cups of regular coffee per day had a 40% lower risk of gallstones compared with men who did not drink coffee.9 In the same report, men drinking at least four cups per day had a 45% reduced risk. Caffeine appears to be the protective ingredient, as decaffeinated coffee consumption was not linked with any protection. People at risk for gallstones who wish to consider increasing coffee drinking to reduce risks should talk with a doctor beforehand. Caffeinated beverages can aggravate symptoms of insomnia, peptic ulcer, panic attacks, and a variety of other conditions.
Constipation has been linked to the risk of forming gallstones.10 When constipation is successfully resolved, it has reduced the risk of gallstone formation.11 Wheat bran, commonly used to relieve constipation when combined with fluid, has been reported to reduce the relative amount of cholesterol in bile of a small group of people whose bile contained excessive cholesterol (a risk factor for gallstone formation).12 The same effect has been reported in people who already have gallstones.13 Doctors sometimes recommend two tablespoons per day of unprocessed Miller’s bran; an alternative is to consume commercial cereal products that contain wheat bran. Bran should always be accompanied by plenty of fluid. Adding more bran may cause gastrointestinal symptoms in some people. If this occurs, consult a doctor.
Gallbladder attacks (though not the stones themselves) have been reported to result from food allergies. The one study to examine this relationship found that all of the participants with gallbladder problems showed relief from gallbladder pain when allergy-provoking foods were identified and eliminated from the diet.14 Eggs, pork, and onions were reported to be the most common triggers. Pain returned when the problem foods were reintroduced into the diet. Doctors can help diagnose food allergies.
Lifestyle changes that may be helpful for gallstones
People with gallstones may consume too many calories15 and are often overweight.16 17 Obese women have seven times the risk of forming gallstones compared with women who are not overweight.18 Even slightly overweight women have significantly higher risks.19 Losing weight is likely to help,20 but rapid weight loss might increase the risk of stone formation.21 Any weight-loss program to prevent or treat gallstones should be reviewed by a doctor. Weight-loss plans generally entail reducing dietary fat, a change that itself correlates with protection against gallstone formation and attacks.22 23
In women, recreational exercise significantly reduces the risk of requiring gallbladder surgery due to gallstones. In a study of over 60,000 women, an average of two to three hours per week of recreational exercise (such as cycling, jogging, and swimming) reduced the risk of gallbladder surgery by about 20%.24
Use of birth control pills significantly increases a woman’s risk of developing gallstones.25 26
Nutritional supplements that may be helpful for gallstones
Vitamin C is needed to convert cholesterol to bile acids. In theory, such a conversion should reduce gallstone risks. Women who have higher blood levels of vitamin C have a reduced risk of gallstones.27 Although this does not prove that vitamin C supplements can prevent or treat gallstones, some researchers believe this is plausible.28 One study reported that people who drink alcohol and take vitamin C supplements have only half the risk of gallstones compared with other drinkers, though the apparent protective effect of vitamin C did not appear in non-drinkers.29 In another trial, supplementation with vitamin C (500 mg taken four times per day for two weeks before gallbladder surgery) led to improvement in one parameter of gallstone risk (“nucleation time”), though there was no change in the relative level of cholesterol found in bile.30 While many doctors recommend vitamin C supplementation to people with a history of gallstones, supportive evidence remains preliminary.
According to one older report, people with gallstones were likely to have insufficient stomach acid.31 Some doctors assess adequacy of stomach acid in people with gallstones and, if appropriate, recommend supplementation with betaine HCl. Nonetheless, no research has yet explored whether such supplementation reduces symptoms of gallstones.
Phosphatidylcholine (PC)—a purified extract from lecithin—is one of the components of bile that helps protect against gallstone formation. Some preliminary studies suggest that 300–2,000 mg per day of PC may help dissolve gallstones.32 33 Some doctors suggest PC supplements as part of gallstone treatment, though the supporting research is weak.34
Are there any side effects or interactions with gallstones?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful for gallstones
Milk thistle extracts in capsules or tablets may be beneficial in preventing gallstones. In one study, silymarin (the active component of milk thistle) reduced cholesterol levels in bile,35 which is one important way to reduce gallstone formation. People in the study took 420 mg of silymarin per day.
According to preliminary research, a mixture of essential oils dissolved some gallstones when taken for several months.36 The greatest benefits occurred when the oils were combined with chenodeoxycholic acid, which is available by prescription.37 However, only about 10% of people with gallstones have shown significant dissolution as a result of taking essential oils. Peppermint oil is the closest available product to that used in the research described above. Use of peppermint or any other essential oil to dissolve gallstones should only be attempted with the close supervision of a doctor.
Are there any side effects or interactions with gallstones?
Refer to the individual herb for information about any side effects or interactions.