[articles.mercola.com]

"This is because we all create something called zonulin in the intestine in response to gluten. This protein, found in wheat, barley and rye, makes your gut more permeable, which allows proteins to get into your bloodstream that would otherwise have been excluded. That then sensitizes your immune system and promotes inflammation and autoimmunity. This kind of gut permeability is also promoted by things like antibiotics and chlorinated water."

Once gluten sensitizes your gut, it then becomes more permeable and all manner of previously excluded proteins—including casein and other dairy proteins—have direct access to your bloodstream, thereby challenging your immune system.

“They’ve been talking about it for years and years (which is now just gaining traction in mainstream medicine) that our health really depends on maintaining a barrier of the intestine from the bloodstream,” Dr. Perlmutter says.

“We now understand that the so-called blood-brain barrier, or that barrier that keeps things out of the brain where they don’t belong, is also affected by gluten, according to new research. It’s a very exciting time when we recognize that our biggest exposure to the environment is actually the lining of our intestines – not our lungs, not our skin. We are in fact very much dependent on the microbiota, the bacteria living in the gut, to maintain our health.”

According to Dr. Perlmutter, much of our current disease burden stems from the fact that we are contaminating our immune systems with proteins to which the human immune system has never, in the history of humankind, been previously exposed to.