Gallbladder and Gallstones
The gallbladder is a small sac-like organ located below the liver. Its primary function is to store and concentrate bile, an important digestive fluid made by the liver. When fat enters the upper portion of the small intestine (duodenum), bile flows from the liver through bile ducts to the duodenum. When the small intestine is empty, bile flows back into the gallbladder for storage. Bile consists of water, cholesterol, fats, bile salts (also called bile acids), and a yellow pigment product known as bilirubin.
Gallstones (cholelithiasis) are the most common gallbladder disorder, and affect about one-fifth of men and one-third of women at some point in their lives.1 Stones form when cholesterol and other elements of the bile are abnormally concentrated or they are in disproportion. Three types of gallstones exist. Pigment stones, comprised primarily of bilirubin, are more common in some populations and parts of the world than in others and occur most frequently among persons who have types of anemia characterized by rapid destruction of red blood cells. Mixed stones, the most widespread type of stone, develop from crystalline particles of cholesterol mixed with other bile substances. Sometimes mixed stones are referred to as cholesterol stones, since they are comprised mostly of cholesterol. However, the third type of stones, comprised of pure cholesterol, is rare.
Symptoms & Diagnosis
About half of all patients with gallstones are asymptomatic, however, you may have heard of, or even had, what many refer to as a gallstone ‘attack,’ an episode of mild to intense pain in the lower or upper right abdomen, which can spread to your right upper back or shoulder blade area. This is the most common presentation. Other symptoms include vomiting, tenderness in the area of the gallbladder, and a low-grade fever. If shaking and chills occur, this usually indicates a bacterial infection in the gallbladder. Sometimes symptoms can increase in severity when a stone blocks a portion of, or the entire, biliary tract. After symptom assessment occurs, abdominal ultrasound or x-ray generally confirms diagnosis.1
Risk Factors
The following are some risk factors for gallstone formation:2,3
- Female gender
- Age over 55 years
- Obesity
- Rapid weight loss
- Diabetes
- High calorie diet
- High cholesterol diet
- Pregnancy
- Gastric bypass surgery
- Maternal family history of gallstones
- Alcoholic cirrhosis
- The following medications: Post-menopausal estrogen, cholesterol-lowering medication
Other Risks
According to a number of scientific studies, patients with Crohn’s disease are at a significantly increased risk of developing gallstones. A recent study demonstrated a two-fold increase in risk, and researchers found that the disease site (namely ileocecal and ileocolonic involvement) was a specific risk factor, as was duration of disease.4 After 15 years of disease activity, Crohn’s patients’ risk of gallstone development rose to 4 times greater than the general population.
Additionally, patients with more and longer hospital stays, a higher number of total parenteral nutrition treatments, and ileal resection had greater risk. However, patients with ulcerative colitis did not have an increased incidence of gallstones.
Treatment
Asymptomatic or uncomplicated gallstones usually do not require treatment. If you have a mild gallstone attack, your doctor may prescribe pain medication, however, after your first incidence, you have a much higher likelihood of repeat attacks. If subsequent episodes occur, then the most direct and effective course of treatment is surgical gallbladder removal (cholecystectomy). The gallbladder is a non-essential organ, and this very safe procedure, usually performed laparoscopically, with minimal incisions, is the most commonly performed bowel surgery in medicine, with approximately 600,000 performed annually in Canada.3,5 Some surgeons are experimenting with gallbladder removal via the vagina in women.6 Without the presence of the gallbladder, bile flows directly from the liver into the small intestine, and this leads to diarrhea in about 1% of patients, although for most this is a temporary effect.7
In patients for whom surgery carries an abnormally high risk, such as the elderly or those with otherwise compromised health, sound waves can be used to breakup the gallstones non-invasively, during a procedure called lithotripsy. Physicians may also prescribe medication to dissolve the stones. These options are less effective treatments than surgery and carry a considerably greater risk of stone recurrence.2
Prevention
Gallstone prevention focuses on specific lifestyle changes that echo common advice for general health and well-being and for reduction of many other disease risk factors.2
- Keep a healthy weight and avoid weight fluctuations. If trying to achieve weight loss, do so slowly, aiming for about a 0.5 kg loss per week.
- Discuss taking post-menopausal hormones with your doctor and consider the pros and cons, as some medications may increase your risk of gallbladder disease.
- Get enough exercise. A number of studies show that regular physical activity correlates with a decrease in risk of gallstone disease in men and women.8
- Eat regular meals containing some fat and plenty of whole grains and fibre and avoid saturated fat and cholesterol. Make sure you get adequate dietary calcium.
Some more specific research looks at the following prevention measures:
Eat more vegetables As part of the large prospective Nurses’ Health Study, researchers discovered a strong link between increased consumption of vegetable protein and a decreased risk of cholecystectomy.9 This research followed animal studies that reported significantly inhibited gallstone formation with higher vegetable protein intake. After controlling for various risk factors including age, body mass index, recent weight change, physical activity, diet and more, this study found that increased vegetable protein intake had a protective effect on gallstone formation independently of total protein intake or intake of animal protein. The authors suggest that “substituting vegetable protein for part of the animal protein supply or other macronutrients in the Western diets could be effective in primary or secondary prevention of gallstones at the earliest stage of crystal formation in humans”. Good vegetable sources of protein are peas, beans, and lentils, soy-based foods such as tofu and soymilk, and nuts and seeds.10 (check out our article on how dietary fibre can reduce your risk for gallbladder surgery).
If you’re a man, try magnesium Supported by numerous previous findings, this editorial in the American Journal of Gastroenterology, indicates that men who consume the most magnesium in their diets have a considerably lower risk of developing symptomatic gallstone disease, compared to men who consume the least amount of magnesium.11 This association was evident for dietary magnesium consumption, but not for those taking supplements, most likely because only a very small percentage of study subjects used magnesium supplements. Furthermore, the presence of asymptomatic gallstones, which form the majority of all gallstones, was not taken into account. Green vegetables, beans and peas, nuts and whole grains are all good sources of dietary magnesium. (note: since the study only looked at male participants, researchers related their conclusions to men only.)
Outlook
Fortunately, most patients function very well without their gallbladder, and thus adequate management of gallstones through surgical removal of the gallbladder is an excellent treatment with very few complications and mild or no side effects in most patients.
A note on gallbladder cancer: Although extremely rare, comprising less than 0.5% of all cancers, gallbladder cancer presents with symptoms similar to gallstone disease: nausea, vomiting, pain, and anorexia. Gallstones are evident in 75% of patients with gallbladder cancer (although the incidence of gallbladder cancer among patients with gallstones is still extremely low at 0.2%). The highest risk is for patients with symptomatic gallbladder disease. Surgery is the only curative treatment for this type of cancer.12