Malabsorption Test

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WHAT IS MALABSORPTION? Malabsorption is the insufficient assimilation of dietary substances due to metabolic malfunctioning in digestion, absorption, or transport. Eating a healthy meal is purposed to give health benefits such as essential minerals and vitamins to the body. A condition where the body isn’t able to assimilate many nutrients from the food you eat… Read More

Malabsorption Test


Malabsorption is the insufficient assimilation of dietary substances due to metabolic malfunctioning in digestion, absorption, or transport.

Eating a healthy meal is purposed to give health benefits such as essential minerals and vitamins to the body. A condition where the body isn’t able to assimilate many nutrients from the food you eat is abnormal and is described as a malabsorption syndrome. This syndrome can cause bloating and diarrhea, thus resulting in serious complications such as a higher chance of infection and bone weakening.


Many factors can lead to malabsorption syndrome, ranging from certain diseases to infections or birth defects. Its causes may include:

  • Lactase deficiency or lactose intolerance.
  • Prolonged use of antibiotics.
  • Diseases of the gallbladder, liver, or pancreas.
  • Diseases due to parasites.
  • Congenital defects such as biliary atresia (when the bile ducts don’t develop normally and prevent the flow of bile from the liver).
  • Other conditions such as cystic fibrosis, celiac disease, chronic pancreatitis, or Crohn’s disease.
  • Damage to the intestines, due to inflammation, trauma, infection, or surgical operation. 
  • Radiation therapy (which may injure the lining of the intestine).
  • Some drugs can injure the lining of the intestine, such as tetracycline, cholestyramine, or colchicines.
  • Certain digestive abnormalities (including the inability of the stomach to produce specific enzymes to digest certain foods or the inability of the body to mix the food with the enzymes and acid produced by your stomach).

Other rare causes include:

  • Topical spruce (caused by intestinal inflammation, which makes it difficult to absorb nutrients from food, particularly folic acid and vitamin B12).
  • Short bowel syndrome (SBS; in which the intestine is shortened, as a result of a birth defect or surgery).
  • Whipple’s disease (related to a bacterial infection).


The signs of malabsorption syndrome classify themselves according to the nutrients involved. These indications may include any of the following listed below:

  • Abdominal discomfort, like gas and bloating.
  • Frequent diarrhea.
  • Light-colored feces.
  • Bad-smelling loose feces.
  • Fatty and bulky feces.
  • Hard-to-flush feces (mainly because they stick to the water closet toilet bowl or float in it).
  • Soft feces.
  • Scaly skin rashes.
  • Weight loss.
  • Weight gain (in children).
  • Undergrowth (in children).
  • Dry hair.
  • Hair loss.
  • Fluid retention (edema).
  • Anemia.
  • Low blood pressure.
  • Muscle wasting.
  • Menstrual abnormality.


(Different Types of Malabsorption Tests)

Certain tests help confirm the diagnosis of malabsorption. 

These malabsorption tests include:

  • Stool Test for Malabsorption (Fat Malabsorption Test)

These can measure fat in a sample of feces. It is the most reliable test because fat is usually present in the feces of persons with malabsorption syndrome. The steps are as follows:

  • The patient is asked to ingest at least 80gm of fat daily.
  • His/her feces sample is collected for 1 – 3 days.
  • The total amount of his/her excreted feces is determined in the laboratory. 

Fat in feces ranges as follows: 

  • Not more than 7gm of fat per day (normal).
  • Not more than 30gm of fat per day (patients with bile acid deficiency and bacterial overgrowth).
  • Not more than 60gm of fat per day (patients with celiac disease).
  • 80 – 100gm of fat per day (severe steatorrhea ─ in patients with pancreatic insufficiency or significant bowel resected).


  • Xylose Absorption or Fructose Intolerance Test

This test evaluates the ability of the intestinal mucosa to absorb. D-xylose is a sugar absorbed across the intestinal mucosa and can be measured in the blood and urine.

  • A patient is made to drink a juice with the xylose.
  • Urine or blood is collected after several hours (about 8 hours).
  • The urine or blood sample is tested in the lab for xylose. 

Low xylose or lactose level in the blood or urine indicates an abnormality of the intestinal mucosa.

  1. Pancreatic Function Tests
  • The patient is made to ingest a chemical called bentiromide.

Bentiromide is broken down by pancreatic enzymes, yielding para-aminobenzoic acid (PABA) as one of the constituents.

  • PABA is absorbed and excreted in the urine.
  • The urine sample is collected and tested.

Low PABA level in urine indicates pancreatic insufficiency. 

Another pancreatic function test examines the bicarbonate and enzyme concentrations.

  • A tube is placed through the nose or mouth of the patient so that its tip is lying next to the opening of the pancreatic duct into the duodenum.
  • Secretions are collected and the content of bicarbonate and enzymes are measured after the pancreas has been stimulated with a hormone called secretin or with a test meal.
  • Pancreatic insufficiency is indicated if the bicarbonate and enzyme concentrations are very low.
  1. Breathing Tests

Breath can be used to test for lactose intolerance.

  • A patient is made to ingest a product containing lactose.
  • The patient’s breath is collected and tested for hydrogen.
  • If the patient’s breath has hydrogen, he/she has lactose intolerance.

If lactose is not being absorbed, it enters the colon. The lactose is broken down by bacteria in the colon, producing hydrogen gas. 

The excess hydrogen gas is absorbed from your intestine into your bloodstream, and then into your lungs. Then you exhale the gas.

  1. SeHCAT Test

This test uses a drug which is a combination of 23-seleno-25 homotaurocholic acid, to detect bile acid malabsorption. This drug is a capsule taken orally.


The risk factors for malabsorption syndrome include:

  • A family history of cystic fibrosis or malabsorption.
  • Drink large quantities of alcohol.
  • Use of some medications, like laxatives or mineral oil, and antibiotics for a prolonged time.
  • Intestinal surgery may shorten a person’s intestine.
  • Travel to the Caribbean, India, or other parts of Southeast Asia.
  • Children with bad stomach flu.


Not getting enough minerals, vitamins, and other nutrients for your body up to keep may lead to serious health complications. When not treated, malabsorption syndrome may lead to:

  • Slower growth and weight gain in children.
  • Greater chance of infections.
  • Low bone density (osteoporosis), an increased risk of bone fractures.
  • Weakened immune system.

Certain nutrients, such as vitamin A and zinc are vital markers to your healthy immune system. A weak immune system can be life-threatening since your body can’t resist any external aggression.


Consult your doctor. Treatment may be dietary and lifestyle changes. Treating the underlying disorders is the only authentic approach to malabsorption syndrome. 


  • Is malabsorption syndrome curable?

Treatment for malabsorption symptoms depends on the cause. Malabsorption tests can diagnose and direct treatment, and you may be put on a special diet of foods that are more easily digested and absorbed. You may also be given supplements to make up for nutrients that aren’t being absorbed well.

  • Can blood tests detect malabsorption?

A complete blood cell (CBC) count may reveal microcytic anemia due to iron deficiency or macrocytic anemia due to vitamin B12 or folate (vitamin B9) malabsorption. Serum iron, vitamin B12, and folate concentrations may help establish a diagnosis.

  • Is there a test for malabsorption?

Tests sometimes ordered include stool test (to measure fat content in feces), breath test (to know lactose intolerance), xylose absorption test (to detect xylose level in the blood or urine), and pancreatic function tests indicating pancreatic insufficiency through low PABA level in urine.

  • What foods cause malabsorption?

In intestinal malabsorption resulting in intestinal disorders, such as celiac disease, gluten protein from wheat, barley, and rye, all trigger your immune system to attack your body. Other examples include lactose intolerance or other enzyme-related conditions.

  • What does malabsorption poop look like?

Symptoms of inability to absorb fats, proteins, certain sugars, or vitamins, may include having light-colored, foul-smelling stools that are soft and bulky, and fatty stools. Most of the time, they stick to the side of the toilet bowl and may be difficult to flush away.