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Overview of Malabsorption


The Manual's Editorial Staff

Last full review/revision Jul 2020| Content last modified Jul 2020
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Food you eat has to be digested before it can go into your body. Digestion breaks food down into its separate parts:

  • Proteins

  • Fats

  • Carbohydrates

Proteins, fats, and carbohydrates are nutrients because they provide nutrition. Other nutrients are:

  • Vitamins and minerals

After food is digested, nutrients go into your body through the walls of your intestines. This is called absorption.

What is malabsorption?

"Mal" means bad. So malabsorption means bad absorption. A problem somewhere in your gastrointestinal (GI) tract keeps you from absorbing one or more kinds of nutrients.

  • Malabsorption can be caused by diseases, surgery on your intestines, or intestinal infections

  • You'll usually lose weight and have diarrhea and smelly stool (poop)

  • After a while, you may get vitamin deficiencies, which may give you a low blood count and feel make you feel sick

  • Doctors often have to do stool and blood tests and sometimes look in your stomach and intestines with a flexible scope (endoscopy)

  • Different causes of malabsorption need different treatments, but doctors usually try to adjust your diet to relieve your symptoms

What causes malabsorption?

Two main problems cause malabsorption:

  • Food isn't digested properly

  • Your intestines can't absorb nutrients

What causes digestion problems?

You won't be able to digest food completely if:

Why can't you absorb nutrients?

You have trouble absorbing nutrients if:

What are the symptoms of malabsorption?

The most common symptom of malabsorption is:

  • Chronic diarrhea

You'll have lots of loose, oily stools that smell worse than usual.

Other symptoms include:

  • Feeling gassy and bloated

  • Losing weight

  • For women, stopped periods

Vitamin and mineral deficiencies can cause:

  • Low blood count (anemia)

  • Easy bruising

  • Tingling of hands and feet

How do doctors diagnose malabsorption?

Doctors usually do:

  • Stool tests to look for unabsorbed fat

  • Blood tests

If these tests show malabsorption, doctors then do tests to look for the cause. They may:

  • Look down your stomach and intestines with a flexible viewing scope (endoscopy)

  • Measure certain chemicals in your breath

  • Take x-rays after you swallow a liquid contrast agent

How do doctors treat malabsorption?

Treatment depends on the cause. Some malabsorption diseases have specific treatments. For example, tropical sprue and Whipple disease are treated with antibiotics.

In general, if you have trouble with only certain foods, doctors will have you avoid them. If you are missing certain digestive enzymes, sometimes you can take enzyme supplements. If you have a vitamin deficiency, you'll take extra vitamins.

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