The malabsorption of commonly occurring mono and disaccharides: levels of investigation and differential diagnoses

Dtsch Arztebl Int. 2013 Nov 15;110(46):775-82. doi: 10.3238/arztebl.2013.0775.


Background: Adverse food reactions (AFR) have has recently attracted increased attention from the media and are now more commonly reported by patients. Its classification, diagnostic evaluation, and treatment are complex and present a considerable challenge in clinical practice. Non-immune-mediated types of food intolerance have a cumulative prevalence of 30% to 40%, while true (immune-mediated) food allergies affect only 2% to 5% of the German population.

Method: We selectively searched the literature for pertinent publications on carbohydrate malabsorption, with special attention to published guidelines and position papers.

Results: Carbohydrate intolerance can be the result of a rare, systemic metabolic defect (e.g., fructose intolerance, with a prevalence of 1 in 25,000 persons) or of gastrointestinal carbohydrate malabsorption. The malabsorption of simple carbohydrates is the most common type of non-immune-mediated food intolerance, affecting 20% to 30% of the European population. This condition is caused either by deficient digestion of lactose or by malabsorption of fructose and/or sorbitol. Half of all cases of gastrointestinal carbohydrate intolerance have nonspecific manifestations, with a differential diagnosis including irritable bowel syndrome, intolerance reactions, chronic infections, bacterial overgrowth, drug side effects, and other diseases. The diagnostic evaluation includes a nutritional history, an H2 breath test, ultrasonography, endoscopy, and stool culture.

Conclusion: The goals of treatment for carbohydrate malabsorption are to eliminate the intake of the responsible carbohydrate substance or reduce it to a tolerable amount and to assure the physiological nutritional composition of the patient's diet. In parallel with these goals, the patient should receive extensive information about the condition, and any underlying disease should be adequately treated.

Publication types

  • Review

MeSH terms

  • Breath Tests / methods*
  • Carbohydrate Metabolism, Inborn Errors / classification
  • Carbohydrate Metabolism, Inborn Errors / diagnosis*
  • Diagnosis, Differential
  • Dietary Carbohydrates / adverse effects*
  • Endoscopy, Gastrointestinal / methods*
  • Feces / chemistry*
  • Humans
  • Malabsorption Syndromes / classification
  • Malabsorption Syndromes / diagnosis*
  • Malabsorption Syndromes / etiology
  • Medical History Taking / methods
  • Ultrasonography / methods*


  • Dietary Carbohydrates

Supplementary concepts

  • Glucose-Galactose Malabsorption