Introduction
Bile is a natural fluid produced by the liver and is required for proper digestion. It comprises acids, proteins, salts, and other substances. It travels from the liver to the gallbladder, where it is stored until one eats. When one eats, the gallbladder contracts, allowing bile to enter the stomach. The acids in bile help break down food and nutrients in the stomach and small intestine so the body can absorb them efficiently. Then, bile acids are reabsorbed back into the bloodstream in the colon so they can be used again.
What Is Bile Acid Malabsorption?
Bile acid malabsorption (BAM) is a condition in which the intestines cannot absorb bile acids properly. This causes an increase in bile acids in the intestines, which can result in watery diarrhea. Bile acids are not always properly reabsorbed, resulting in BAM. As a result, more bile acid in the colon can cause diarrhea and watery stools; BAM is also known as bile acid diarrhea.
What Causes Bile Acid Malabsorption?
In some cases, there is no exact explanation for why the colon does not fully reabsorb bile acids. This is referred to as primary BAM. If BAM is caused by an underlying condition such as irritable bowel syndrome (IBS-D) and diarrhea, it is known as secondary BAM.
Other secondary BAM-related conditions include:
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Crohn's disease (chronic inflammation of the gastrointestinal tract extending from stomach to anus).
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Celiac disease (abnormal immune reaction due to consumption of gluten).
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Small intestine diseases.
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Pancreatic diseases.
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Bacterial overgrowth in the small intestine.
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Medication side effects can also contribute to BAM.
What Are the Types of Bile Acid Malabsorption?
There are three types of bile acid malabsorption, depending on the cause of the condition:
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Type 1: This type of BAM can occur following the surgical removal of a portion of the small intestine. Type 1 BAM can also be caused by inflammatory bowel diseases such as Crohn's disease, radiation therapy, etc.
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Type 2: BAM is also known as primary or idiopathic BAM because it has no apparent cause but occurs spontaneously. Research studies suggest it is due to improper signaling between the intestine and the liver.
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Type 3: This third type of BAM is caused by conditions such as chronic diseases, radiation therapy, celiac disease, chronic pancreatitis, etc.
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Type 4: This type of bile acid malabsorption is caused due to increased bile production as an adverse effect of taking Metformin.
What Are the Symptoms of Bile Acid Malabsorption?
Diarrhea is the most common symptom of BAM. Frequent, watery stools make managing this condition difficult and sometimes embarrassing. People with BAM are more likely to have stools that are:
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Painful.
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Watery.
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Urgent or uncontrollable.
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Yellow and particularly smelly.
Furthermore, BAM can cause:
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Cramps in the stomach.
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Flatulence.
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Weight gain or loss.
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Bloating.
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Fatigue.
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Difficulty concentrating.
How Is Bile Acid Malabsorption Diagnosed?
Bile acid malabsorption is difficult to diagnose. Approximately 44 percent of people had symptoms for at least five years before diagnosis. A "therapeutic trial" is the most common method of diagnosing BAM in the United States. BAM patients are given a bile acid sequestrant, a medication that helps treat the condition. However, this medication may not be effective for everyone with BAM; however, some people, regardless of their condition, cannot tolerate it. According to studies, this diagnostic approach is useful when other tests are unavailable; it is not a definitive method of identifying BAM.
Blood tests are a new way for doctors to determine whether or not a patient has bile acid malabsorption. They may examine the blood for chemical precursors of bile acid and specific hormones associated with high bile acid levels. However, more research in this area of blood testing is required.
How Is Bile Acid Malabsorption Treated?
Medication and dietary changes are typically used to treat bile acid malabsorption. Most people with BAM find that combining the two produces the best results. Treating the underlying condition can often eliminate symptoms of secondary BAM.
1. Medication
A bile acid binder is the most common medication used to treat BAM. It binds to bile acids in the digestive tract, reducing their effect on the colon. Bile acid binders are usually very effective in treating diarrhea caused by BAM. Bile acid binders that are commonly used include:
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Cholestyramine (Questran).
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Colestipol (Colestid).
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Colesevelam (Welchol).
2. Diet
Dietary changes may also help reduce diarrhea episodes in people with BAM. Bile is necessary for fat digestion. This means that when one eats a lot of high-fat foods, the body has to produce more bile and bile acids.
A low-fat diet can lessen the amount of bile acid produced by the body, causing less of it to reach the colon. Lower levels of bile acids in the colon lessen the chances of having diarrhea in people with BAM.
The following foods must be avoided to reduce fat intake:
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Butter and margarine.
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Mayonnaise.
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Fried or breaded foods.
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Baked goods, such as cookies and pastries.
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Lunch meats, sausage, bacon, or other processed meats
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Full-fat dairy products, such as sour cream
The body requires some fat to function properly, hence substituting healthier fats in the diet can be beneficial, such as:
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Avocados.
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Fatty fish like salmon and sardines.
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Nuts like cashews and almonds.
While these fats are better for the body, people with BAM should still consume them in moderation. A registered dietitian or nutrition counselor may be recommended by the doctor so that one can work together to develop a diet plan that fits their lifestyle and help manage their symptoms.
Conclusion
Bile acid is produced by the liver and helps in the breakdown of food and nutrients in the stomach and small intestine so the body can absorb them efficiently. Bile acids are reabsorbed into the bloodstream in the colon so they can be used again. Bile acid malabsorption occurs when the intestines cannot absorb bile acids adequately. This increases the bile acid content in the intestines, which can cause watery diarrhea. Most people with bile acid malabsorption respond to treatment and can use medications and lifestyle changes to prevent or manage their symptoms. If the underlying condition causing BAM is identified, it may be possible to manage the condition by treating the underlying issue.
