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L’Accademia del Fitness part of the MALT system) it has been confirmed that an altered intestinal absorption can condition lacrimal film composition creating the sensation of “extraneous body”, red eyes and ocular tiredness with mute eye objectivity. Eyesight can therefore really represent an exact mirror of the general health situation. It is by now acknowledged that integral intestinal mucosa is responsible for barrier selectivity, playing a fundamental role not only of absorption, but also in defence mechanisms. Selectivity is also assured by the balance between the various bacterial populations which all together constitute the intestinal ecosystem. Dr Maria Letizia Primo Nutritionist –Legal Doctor- Psychiatrist

TEST OF INTESTINAL PERMEABILITY Integrity of intestinal mucosa can be evaluated noninvasively by means of measurement of urinary excretion ratio of two test substances submitted orally. These substances present a different permeability index: a lager molecule, a disaccharide (lactulose or cellobiose) and a smaller one, a monosaccharide (mannitol or L-rhamnose). They are hydrosoluble, non-absorbable molecules which do not suffer metabolisation or degradation by intestinal flora. They are not submitted to mechanisms of active transport or facilitated diffusion and, if absorbed, (in conditions of abnormality) they are completely eliminated through the kidneys (dosage permitting). The monosaccharide of smaller dimensions passes through the mucosa across the cells through enterocyte hydrophilic pores by virtue of its small dimensions, whereas the disaccharide diffuses with greater difficulty, as it can pass through the barrier only at intercellular tight junctions, generally not very permeable to macromolecules. These sugars will behave paradoxically in patients who have damaged intestinal mucosa, that is, larger molecules (disaccharide) will pass more easily than smaller ones (monosaccharide). In the former, the increase of monosaccharide/ disaccharide urinary excretion ratio is above all due to a decrease in monosaccharide absorption, whereas in inflammatory diseases with compromised mucosa (MC and RCU) the increase is due to greater macromolecule permeability. Although the sensibility of this test is sufficiently high (90%), its specificity is very low (54%), since similar results are obtainable in every condition of altered intestinal permeability.

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N. 10 - July 2013  

Wellness & Antiaging magazine

N. 10 - July 2013  

Wellness & Antiaging magazine