Diet and Lifestyle Interventions
Dietary factors play an important role in the development of cholesterol gallstone disease. In general, a high-calorie, high-fat diet characterized by high intakes of sugar, refined carbohydrates, saturated fat, cholesterol, and trans fats has been linked to an increased risk of gallstones and their complications (Compagnucci 2016; Di Ciaula 2017; Di Ciaula 2013; Setiawan 2017). On the other hand, a diet rich in fiber, fruits and vegetables, plant proteins, and monounsaturated and polyunsaturated fats is protective (Di Ciaula 2017; Gaby 2009; Sachdeva 2011). A Mediterranean-style diet, which emphasizes fruits, vegetables, seafood, legumes, and olive oil, was associated with reduced cholecystectomy risk in a study in French women (Barre 2017). A high-fiber diet has been found to prevent gallstones in obese patients undergoing rapid weight loss (Sulaberidze 2014). Some evidence suggests that some of these dietary factors do not appear to impact gallstone risk in pregnant women (Mathew 2015; Basso 1992).
Judicious Weight Loss
Weight loss is an important strategy for reducing the risk of gallstones in overweight or obese individuals, yet the risk of gallstones increases when weight is lost rapidly (Portincasa 2016). In a study with more than 6,000 people participating in one of two weight loss programs, those on a 500 calorie per day diet for three months, followed by nine months of weight maintenance, were three times more likely to need hospitalization for symptomatic gallstones or cholecystectomy for gallstones than those who started with a 1,200–1,500 calorie per day diet. Although the rates of gallstone-related hospitalization were relatively low in both groups, at 1.5% per year in those on the very-low-calorie diet and 0.4% per year in those on the low-calorie diet, the results suggest that the health benefits of weight loss may be best achieved through modest calorie restriction (Johansson 2014).
Generally, weight loss of greater than 24% of initial body weight and at a rate greater than 1.5 kg (about 3.3 pounds) per week has been identified as a risk factor for gallstones, but the risk may be mitigated by controlling the rate of weight loss, reducing the length of the overnight fast, and keeping a small amount of fat (at least 7 grams per day) in the diet to improve gallbladder motility (Erlinger 2000).
Coffee and tea appear to reduce the risk of gallstones, possibly by stimulating gallbladder activity (Zhang 2006; Zhang 2015). Moderate alcohol intake, which may stimulate gallbladder emptying, has also been associated with a lower gallstone risk (Mostofsky 2016; Walcher 2010). Foods that contain polyunsaturated fats (eg, fish) and monounsaturated fats (eg, olive oil and nuts) appear to be protective as well (Misciagna 1996; Brown 2017; Alarcon de la Lastra 2001). In a study that followed over 80,000 women for 20 years, eating five or more servings of nuts per week was associated with a 25% lower risk of cholecystectomy (Tsai 2004a). Similarly, a study that followed over 43,000 men for more than 10 years identified a 30% lower gallstone risk in those eating five or more servings of nuts per week compared with those who rarely or never ate nuts (Ros 2010; Tsai 2004b).
Garlic, onions, fenugreek, and components from other dietary spices including turmeric, cayenne, and black pepper have each demonstrated the ability to prevent and dissolve cholesterol gallstones in animal studies. Preclinical research suggests they reduce cholesterol saturation in bile and inhibit the first stage of cholesterol crystal formation (Song 2015; Shubha 2011; Reddy 2011a; Reddy 2011b; Vidyashankar 2010a; Vidyashankar 2010b).
The “gallbladder flush” is a folk remedy for gallstones that has been popularized through natural health websites and books. The process recommended for gallbladder flushing varies, but usually entails a 12 to 24-hour fast, ending in the evening with the ingestion of a large volume of olive oil and lemon juice. Typically, anywhere from 2/3 to 2 cups of olive oil and 1/3 to 1/2 cup of lemon juice are ingested over several hours. The expectation is that gallstones will be passed the following morning (Sies 2005; Gaby 2009).
In one case report, a number of firm, green globules collected by an individual who had performed a gallbladder flush were analyzed and found to have none of the major components of gallstones—cholesterol, bilirubin, or calcium. Instead, they were composed mainly of fatty acids, presumably from the olive oil itself. Further examination suggested that the globules may have been soaps created by the action of digestive enzymes on the olive oil-lemon juice combination (Sies 2005). Nevertheless, there are several reports of cases in which fewer gallstones were seen on ultrasound after, compared with before, gallbladder flushing (Gaby 2009).
To date, the various methods promoted to “flush” gallstones have not been validated in controlled clinical trials and are not evidence-based.
A sedentary lifestyle increases the risk of cholesterol gallstones, while being physically active decreases the risk (Stinton 2012). Physical activity may prevent cholesterol gallstone formation by improving gut motility and through positive effects on cholesterol metabolism (Pak 2016). A systematic review and meta-analysis that included eight studies and a combined total of almost 7,000 participants concluded that those with the highest physical activity level had a 25% lower risk of gallbladder disease, including gallstones and cholecystitis, than those with the lowest physical activity level (Aune 2016). Exercise may prevent silent gallstones (Henao-Moran 2014) as well as gallstone complications (Shabanzadeh, Sorensen, Jorgensen 2017a). Two to three hours of recreational physical activity each week may reduce the risk of cholecystectomy by about 20% (Pak 2016).