Intestinal permeability in patients with adverse reactions to food

Dig Liver Dis. 2006 Oct;38(10):732-6. doi: 10.1016/j.dld.2006.06.012. Epub 2006 Jul 31.


Background: An abnormal intestinal permeability could contribute to establish an altered sensitivity to food-allergen.

Aim: To evaluate the intestinal permeability in subjects with adverse reactions to food on allergen-free diet.

Subjects: Twenty-one patients with food allergy and 20 with food hypersensitivity on allergen-free diet were enrolled and divided in four groups according to the seriousness of their referred clinical symptoms when they were on a free diet.

Methods: Intestinal permeability was evaluated by Lactulose/Mannitol ratio urinary detection determined by anion-exchange chromatography.

Results: Statistically significant different Lactulose/Mannitol ratio was evidenced in subjects with food allergy (p=0.003) or hypersensitivity (p=0.0008) compared to control patients. The correlation between Lactulose/Mannitol ratio and the seriousness of clinical symptoms, by using Spearman test, was statistically significant for food allergy (p=0.0195) and hypersensitivity (p=0.005) patients.

Conclusions: The present data demonstrate that impaired intestinal permeability, measured in our conditions, is present in all subjects with adverse reactions to food. In addition, for the first time, we report a statistically significant association between the severity of referred clinical symptoms and the increasing of Intestinal Permeability Index. These data reveal that intestinal permeability is not strictly dependent on IgE-mediated processes but could better be related to other mechanisms involved in early food sensitisation, as breast-feeding, or microbial environment that influence the development of oral tolerance in early infancy.

MeSH terms

  • Adolescent
  • Adult
  • Case-Control Studies
  • Female
  • Food / adverse effects*
  • Food Hypersensitivity / metabolism*
  • Humans
  • Intestinal Absorption / physiology*
  • Intestinal Mucosa / metabolism*
  • Intestines / physiopathology
  • Lactulose / urine
  • Male
  • Mannitol / urine
  • Middle Aged
  • Permeability


  • Mannitol
  • Lactulose