Bile acid is a liquid substance your liver produces to aid in food digestion. Your body usually releases bile at the correct levels based on the food you eat. But sometimes your body produces too much bile or isn’t able to use it correctly, resulting in bile acid malabsorption (BAM).
Understanding Bile Acid Malabsorption
When too much bile acid from your stomach enters your colon, it leads to:
- Watery bowel movements
- A sense of urgency when you need to go
- Incontinence or leaking
Bile acid is linked with diarrhea but goes underrecognized and underdiagnosed as a cause of chronic diarrhea. Around one-third of people who are diagnosed with irritable bowel syndrome with diarrhea (IBS-D) also have bile acid malabsorption.
Bile acid malabsorption isn't a stand-alone condition. It's often associated with conditions like Crohn's disease. It's also often accompanied by other health conditions. For example, around 50% of people who have chronic or recurrent diarrhea, also called functional diarrhea, experience bile acid malabsorption. Around 35% of people with large intestine inflammation, also called microscopic colitis, are affected by bile acid malabsorption. But bile acid malabsorption is often forgotten when diagnosing diarrhea.
If you have chronic diarrhea, be sure to bring up the possibility of bile acid malabsorption with your doctor. By having your stool assessed for bile, you may save time and worry over more invasive tests like colonoscopies.
What Is Bile?
Bile is a yellow-green bodily fluid that has two primary functions. Bile helps break down fats in your stomach when food is digested. It also carries waste out of your digestive system. There's a salt component in bile that breaks down fat from food, absorbs it, and moves it into your stool for removal.
Your liver creates bile using special cells. Your bile ducts collect the bile. It then moves through your hepatic duct, joining your cystic duct at your gallbladder and becoming the common bile duct.
Through the digestive process, around half of your bile is stored in your gallbladder, a small organ located just underneath your liver. When you eat, your gallbladder should release the right amount of bile into your stomach to break down fat content. Your gallbladder manages the amount of bile that gets released based on how much your stomach needs for digestion.
Diagnosing Bile Acid Malabsorption
Bile acid malabsorption affects around 1% to 2% of people in the U.S. There are two tests available in the U.S. for diagnosing bile acid malabsorption.
Fecal bile acid test. Your doctor completes a 48-hour stool collection test. If you have chronic diarrhea, you’re likely to have higher levels of primary bile acids, cholic acid, and chenodeoxycholic acid, each associated with irritable bowel syndrome with diarrhea.
Serum 7αC4 test. Your doctor asks you to fast, or stop eating for a period of time, and uses a serum designed to reveal increased bile acid in your stool. The downside to this test is that you may receive a false positive or false negative if you have liver disease or are taking statins.
Treating Bile Acid Malabsorption
Medication. Cholestyramine is the primary medication prescribed for conditions like bile acid malabsorption. It's designed to break down in your colon to improve symptoms of chronic diarrhea.
Surgery. If lifestyle changes and medication don’t help your symptoms, your doctor may recommend surgery to remove your gallbladder. In addition to bile concerns, this surgery may be used to solve:
- Gallstones in your gallbladder, also known as cholelithiasis
- Gallstones in your bile duct, also known as choledocholithiasis
- Gallbladder inflammation, also known as cholecystitis
- Persistent gallbladder polyps impacting the tissue that surrounds your gallbladder
- Pancreas inflammation, also known as pancreatitis
The surgical procedure for gallbladder removal is called a cholecystectomy. A surgeon makes minimally invasive incisions to take your gallbladder out. A cholecystectomy is generally a low-risk procedure. Most people go home the same day, following a period of monitoring. If the surgeon needs to make a larger incision, you may have an extended healing timeline.
Diet changes. There isn’t a specific diet to help with the production of bile acid. But because bile releases to break down fat in foods, consuming less fat in your diet may help. It’s important to avoid greasy foods and fatty sauces.
You may eventually be able to enjoy all your favorite fatty foods again. But in the short term, you should cut out fat to allow your biliary tract to heal. Ask your doctor for a referral to see a dietician if you're unsure what to eat.
Dieticians can help you research food alternatives to high-fat foods and trade them out for low-fat or fat-free foods. Before you eat, make sure to check package nutrition labels. Stick to serving sizes, so you don’t overeat.
You can also bulk up your stool by eating more fiber. Too much fiber at once may cause cramping and gas. Slowly incorporate more fiber over a week or two to normalize the condition of your bowel movements.