Losing The Barrier To Disease
So, what does this all amount to? Intestinal permeability caused by either bacterial overgrowth or gluten (both of which are heavily influenced by diet) may be a key early step to set the body up for many chronic illness.
But is there any research? Fortunately, this is where I have to start using more drawers in my research cabinet.
Higher zonulin levels and intestinal permeability have been associated with and often precede many autoimmune conditions including type 1 diabetes,16, 30, 31, 32, 33celiac disease,17, 28, 34 multiple sclerosis,35, 36 rheumatoid arthritis,37, 38ankylosing spondylitis,37, 39 and Crohn’s disease.40, 41Eating wheat has been directly linked to diabetes.31, 42, 43, 44
A popular theory of autoimmune disease – called the molecular mimicry theory – proposed that autoimmune disease is initiated by viruses that mimic our bodies.26, 27 Dr. Fasano and his group suggested instead that dietary antigens passing through a leaky gut may be the environmental trigger. To test their theory, they were able to use a zonulin inhibitor to reduce the severity of celiac disease symptoms in humans 28 and the incidence of type 1 diabetes in mice.29
Intestinal permeability isn’t just associated with autoimmune conditions. Permeability may affect asthmatics by increasing their exposure to allergens.45, 46 Elevated zonulin levels have been found in irritable bowel disease 47, 48 and cancer.49, 50Even schizophrenia has recently been linked to gluten consumption and zonulin levels.51, 52
But a final question remains.
In a world where most people reach for a bagel and toast as soon as they get out of bed, intestinal permeability may just be a part of western life that gets an unfair rap by association. In other words, is it too easy to just link permeability with chronic disease? Does it really play a role?
In his 2011 review of zonulin and disease, Dr. Fasano addressed this question pointing out a number of studies where symptoms and incidence rates were reduced when gluten was removed from the diet or when zonulin’s effects were blocked.6
Wheat, a no-no for any good Paleo dieter, was clearly opening doors.
Read The Wheat Series Part 3: Setting Off the Bacterial Alarm Bells – With or Without the Bacteria HERE
References
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