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Dietary Fiber and Intestinal Permeability


PR activist
Fiber supplements have complex effects on gut permeability and bacterial composition. Low fibre diets increase permeability. Dietary supplementation with insoluble fibre, such as pure cellulose, decreases permeability. Dietary supplementation with highly soluble fibre sources, such as fruit pectin or guar gum, has a biphasic effect. At low levels they reverse the hyperpermeability of low residue diets, probably by a mechanical bulking effect which stimulates synthesis of mucosal growth factors. At high levels of supplementation, they produce hyperpermeability, probably by inducing synthesis of bacterial enzymes which degrade intestinal mucins[148-151]. For maximum benefit with regard to intestinal permeability, dietary fibre supplementation should therefore contain a predominance of hypoallergenic insoluble fibre.



Senior Member
"FOS fermentation increased fecal wet weight, bifidobacteria, lactobacilli, and lactic acid. Consumption of FOS increased flatulence and intestinal bloating."

When I have a lot of soluble fiber, this happens.

I like Dr. Galland, he seems to not have a bias, recommending whatever works best.

That's a mighty large list of resources.


Senior Member
This is good to hear about insoluble fibre, and yet, I greatly improved my 30+ years of IBS-C with lots of daily acacia powder over a one year period. It's soluble fibre. Improved my IBS by about 80%.

Be wary that insoluble fibre really aggravates IBS for many people. When I had IBS, insoluble fibre gave me terrible pains, bloating, etc, which is very common.

I can now eat both type of fibre with no problems but did do other treatments after the acacia too.