I think it is about intestinal permeablitity and subsequent food sensitivities (causing IBS symptoms for many) for some people with MS.

There is a lot of new research being done right now on intestinal permeability and its relation to autoimmune disease. In celiac disease, the only autoimmune disease with KNOWN cause... ingestion of gluten directly causes intestinal permeability by destroying the intestinal villi, and triggering autoimmunity that can target pretty much any organ in the body. They are looking at whether gluten may be involved in other autoimmune disease as well, especially T1DM, but also MS, RA, and others. There was just study that came out yesterday about this.

Tight junctions, intestinal permeability, and autoimmunity.
http://www.ncbi.nlm.nih.gov/pubmed/19538307

However, research on this goes back further than this study. Dr. Fasano, who authored the article above, discovered the protein zonulin several years back. He found people with autoimmune diseases have higher levels of zonulin, and zonulin performs the "gatekeeping" function of the intestinal barrier as well as the blood brain barrier. Leaky gut and leaky brain. Ingestion of gluten increases zonulin levels in EVERYONE who eats gluten, but the levels appear higher in those with autoimmune disease. And... there may be other factors that cause increased permeability of the intestinal barrier... that may also play a role in the development of autoimmune disease. Research ongoing.

Here are some links to some of the info on zonulin and the intestinal barrier.
http://jccglutenfree.googlepages.com/zonulin

If you are really interested.. you can see more studies looking at food sensivity and autoimmune disease here:
http://jccglutenfree.googlepages.com...oimmunedisease
http://jccglutenfree.googlepages.com/crohn's,ibd,ibs

Gluten and casein sensitivity may factor into the development of TIDM, too. Vitamin D deficiency is the other big thing they are relating to autoimmunity.

So... there is a lot going on in th research... but the bottom line is that the increase of IBS is likely related to increased intestinal permeability found in many various autoimmune disease patients. (which causes food sensitivity... and possibly systemic immunological reactions in predisposed individuals)

This line of research is the basis for much of what the people at MS-Direct are basing their dietary recommendations upon.... but I don't want to speak for them. I don't have MS... my family is gluten sensitive... which is how these paths connect for me. http://jccglutenfree.googlepages.com/multiplesclerosis

Cara