Gallstones Explained
By Dr. Lee Ser Yee
Worried about getting gallstones? And what actually are gallstones?

Dr. Lee Ser Yee, Senior Consultant Hepatopancreatobiliary Surgeon at Surgical Associates based in Mount Elizabeth Hospital explains what gallstones are, who is at risk of gallbladder disease and how to prevent it.

What is the gallbladder?

The gallbladder is a small organ in your upper right abdomen which lies beneath the liver and is connected to the bile duct. The gallbladder stores a yellowish liquid produced by the liver called bile that helps your body digest oily and fatty food. Before a meal, the gallbladder may be filled with bile and is about the size of a small pear. During and after meals, the gallbladder squeezes the stored bile into the small intestine through a tube called the common bile duct. In another words, the gallbladder functions as a storage organ for bile and is thus not essential for life, as the bile produced by the liver will still flow into the intestines without the gallbladder.

Anatomy of Biliary Tree

What are gallstones?

Small pebble-like deposits called gallstones can form in the gallbladder. Normally, bile acids and proteins prevent the formation of stones, however, when there is an imbalance in the bile components, gallstones can form.

There are several types of gallstones – pigment stones, cholesterol stones and mixed stones.

  • Pigment stones tend to develop in patients with liver cirrhosis, biliary tract infections, or hereditary blood disorders like haemolytic anaemia.
  • Cholesterol stones are formed when bile contains too much cholesterol or bilirubin, when there are not enough bile salts, or when the gallbladder does not empty completely. Cholesterol stones were more commonly seen in western world.
  • Over time, cholesterol or pigment stones may accumulate a proportion of calcium, producing mixed gallstones. In Asia, due to the change in lifestyle and dietary habits, cholesterol or mixed stones are common.

Who are at risk of gallstones?

While it is not known why such imbalances in the bile components occur, some people are more prone to develop gallstones. Some of the reasons are:

  • Patients over 40 - 50 years of age as compared to younger patients.
  • Women are twice as likely as men to develop gallstones due to higher oestrogen levels. Excess oestrogen after pregnancy, hormone replacement therapy and oral contraceptive pills tend to increase cholesterol levels in bile.
  • Gallstones tend to run in families, suggesting a genetic link. The underlying mechanism is still unclear and likely due to a variety of factors.
  • Obesity is a major risk factor for gallstones. Several factors such as a high-fat diet, diabetes, a sedentary lifestyle, and other co-existing medical conditions all play a part.
  • A diet high in cholesterol and fat but low in fibre increases the risk of gallstone formation.
  • Diabetic patients have higher fatty acids, which increases their risk of gallstones. They also tend to experience more severe infections and sometimes may have an unusual presentation like lack of fever or pain (“silent” infection).
  • While these drugs lower blood cholesterol, they increase the amount of cholesterol secreted into the bile, hence increasing gallstone formation.
  • Patients who have certain blood disorders, liver cirrhosis, Crohn’s Disease
  • Patients who are on prolonged intravenous feeding or certain medications might also be at a higher risk for developing gallstones and gallbladder disease.”

How can one prevent gallstones and gallbladder disease?

By modifying your lifestyle, you can potentially lower your risk.

  • Fats, especially saturated fats found in meats, butter and animal products, are associated with gallstone attacks.
  • Choose monounsaturated fats (e.g. olive oil) or omega-3 fatty acids (commonly found in fish or canola oil) instead.
  • Plenty of fruits and vegetables help too.
  • Some studies have found that a cup of coffee a day can lower the risk of gallstones as caffeine in coffee can stimulate gallbladder contractions and lower the cholesterol.
  • Some studies have found that while limited and moderate alcohol intake reduces the risk of gallstones, but heavy drinking may do the opposite.
  • It is important to highlight that pregnant women and those with liver disease should avoid alcohol.
  • Regular exercise and healthy balanced diet will minimise many of the risk factors of gallstones.

To know more about the treatment of gallstones and gallbladder disease, please read - Treatment of Gallstones

“Gallstones is a common condition. If your gallstones cause pain and discomfort or have caused health problems, seek medical advice early. Surgery in patients with problematic gallstones can help prevent future problems and potentially life-threatening complications such as inflammation of the pancreas (pancreatitis) or infection of the bile ducts (cholangitis)”