Malabsorption is difficulty digesting or absorbing nutrients from food.

Many diseases can cause malabsorption. Malabsorption is usually the inability to absorb certain sugars, fats, proteins, or vitamins from food. It can also involve a general malabsorption of food.

Some of the causes of malabsorption include:

• Abetalipoproteinemia
• AIDS
• Biliary atresia
• Celiac disease
• Certain medications (cholestryramine, tetracycline, some antacids, some medications used to treat obesity, colchicine, acarbose, phenytoin)
• Certain types of cancer (lymphoma, pancreatic cancer, gastrinomas)
• Certain types of surgery (gastrectomy with gastrojejunostomy, surgical treatments for obesity, partial or complete removal of the ileum)
• Cholestasis
• Chronic liver disease
• Chronic pancreatitis
• Cow's milk protein intolerance
• Crohn's disease
• Cystic fibrosis
• Damage from radiation treatments
• Lactose intolerance
• Parasites
  • Giardia lamblia
  • Necator americanus (hookworm)
  • Strongyloides stercoralis
• Shwachman-Diamond syndrome (a genetic disease affecting the pancreas and bone marrow)
• Soy milk protein intolerance
• Whipple disease

Vitamin B12 malabsorption may be due to:

• Juvenile pernicious anemia
• Tapeworm (diphyllobothrium latum)

Malabsorption of vitamins can occur even without diarrhea.