Who is at Risk for Gallstones and What Causes Them to Occur?

People with gallstones often blame fatty foods for their recurrent pain. But are rich meals more likely to cause gallbladder attacks than low-fat foods? "It's logical, but not proven," says Mayo Clinic gastroenterologist Dr. Johnson L. Thistle. "We know that fat makes the gallbladder contract harder and longer than other nutrients do. Yet research has failed to prove that eating fatty foods consistently causes attacks, or that eating a low-fat diet guarantees pain relief."

Gallstones - round lumps of solid matter in the gallbladder or bile duct - are common. Probably close to 25 percent of women and 10 percent of men in the United States develop them. Gallstones form when there's an imbalance in the ratio of substances contained in bile. (Bile is a liquid that's made in your liver and stored in your gallbladder. It carries waste products away from your liver and helps digest and absorb fats.) About 80 percent of gallstones are made primarily of cholesterol. If your liver secretes an increased amount of bile acid, bile becomes saturated with cholesterol. As cholesterol crystallizes from bile, it eventually forms a solid lump or stone.

Most people with gallstones have no symptoms. Indigestion aggravated by fatty foods, heartburn, belching, bloating and flatulence, symptoms frequently blamed on gallstones, aren't unique to gallbladder disease and are no more common in people with gallstones than in those without.

True gallbladder disease causes pain that strikes suddenly in the abdomen, particularly in the upper, middle, or right side. Food passing from your stomach to the small intestine causes the gallbladder to contract and expel bile into the intestine. If a stone blocks the exit of bile, the gallbladder keeps squeezing to push bile through. This builds pressure, causing a sharp, steady pain that lasts from 15 to 30 minutes or longer.

The pain subsides when the gallbladder relaxes, allowing the stone to fall or pass into the intestine You may remember having a gall gallbladder attack last week after eating three slices of double cheese pizza. But you may forget that yesterday's hot fudge sundae left you symptom free. How the gallbladder reacts to a specific meal varies from person to person. And even the same person responds differently to the same foods on any given day.

What should you do about recurrent gallbladder attacks? See your doctor about treatment options. Meanwhile, Thistle recommends: "Avoid fatty foods, especially large, rich meals late in the evening. There's no guarantee that avoiding a high-fat diet will prevent an attack. But because fat can force maximal contraction of the gallbladder, rich foods may increase the chance for a stone to get stuck in the bile duct"

The person with gallstones often typifies the four Fs - fat, female, forty and fair. Despite some flaws in this inelegant description, it does suggest why you or someone you know may develop gallstones:

• Obesity. In overweight persons, the liver produces more cholesterol, significantly increasing the risk of gallstones.

• Sex. Two to three times more women develop gallstones than men. The female hormone estrogen increases the liver's secretion of cholesterol.

• Age. Saturation of bile with cholesterol increases soon after puberty, leading to a gradual rise in the prevalence of gallstones with age in both men and women. There's nothing special about age 40, but many doctors find it's a common time when symptoms appear.

• Heredity. Having fair skin may mean a higher risk of gallbladder disease (gallstones are particularly common in Sweden). But Native Americans have the highest rate of gallstones.

• Prescriptions. Taking estrogen after menopause or as an oral contraceptive roughly doubles the risk of gallstones. Two cholesterol-lowering drugs, clofibrate (Atromid-S) and gemfibrozil (Lopid), are linked to gallstones. As they lower blood cholesterol and triglyceride levels, they increase the liver's secretion of cholesterol. (A drop in the amount of cholesterol in your blood may signal your liver to make more.)

• Rapid weight loss. Quickly losing a large amount of weight with approaches such as stomach stapling or very low-calorie diets saturates bile with cholesterol and may lead to swift development of gallstones.

Sources:

Gomez, Jones Coping With Gallstones (Overcoming Common Problems Series) 2000

Janowitz, Henry D. Indigestion: Living Better with Upper Intestinal Problems from Heartburn to Ulcers and Gallstones 1994