Google the term “leaky gut” and many websites containing an abundance of information come up.

To help separate the accurate from the not so accurate information, Daniel Leffler, MD, MA, Director of Clinical Research at The Celiac Center at Beth Israel Deaconess Medical Center in Boston graciously agreed to answer some questions.

What exactly is meant by the term “leaky gut?”
The cells lining the intestine are linked together by a complex of proteins known as “tight junctions.” These exist throughout the entire intestinal tract but cells are bound more tightly together in some areas.

These barriers are important ways that your body regulates what comes in and out of the intestinal lining. It has been suggested that if these tight junctions are not working well, proteins and even microorganisms might be able to get into the body past the intestinal lining causing disease or symptoms. This is what is referred to as “leaky gut” or increased intestinal permeability.

What causes leaky gut?
Many things have been shown to weaken tight junctions including gastrointestinal infections, medications such as aspirin or ibuprofen, systemic illnesses such as liver disease, pancreatitis or severe infections, and of course gastrointestinal inflammatory disorders such as inflammatory bowel disease, celiac disease and some types of irritable bowel syndrome.

What diagnostic tests are available for leaky gut?
Currently there are no clinically available proven tests for leaky gut. Testing is sometimes done as part of research studies, but there is currently no good evidence that testing clinically is reliable or helpful.

What is the treatment of leaky gut?
There is no specific treatment for leaky gut other than when possible removing the underlying cause of the dysfunction. Medications are being tested that may help tight junction function.

However, it is important to remember that it is not at all clear whether leaky gut is a cause of illness, a complication of illness or a just a result of illness. For example in celiac disease, we do not know whether a problem with tight junctions leads to the development of celiac disease and possibly other autoimmune disorders (cause of illness), occurs due to celiac disease and then causes other medical problems (complication of illness), or occurs secondary to celiac disease inflammation possibly worsening symptoms but otherwise not of primary concern.

What role does leaky gut play in celiac disease?
Although not entirely clear, it is most likely that tight junctions in celiac disease are damaged secondary to the general intestinal inflammation. Once damaged, they may allow fluid to leak out worsening diarrhea and abdominal symptoms. It is also theorized that in some patients an initial injury to the tight junctions from an infection might allow enough gluten in to cause celiac disease in the first place.

Do all persons with celiac disease by definition have leaky gut?
All patients with active celiac disease will have some degree of leaky gut.

Among persons with celiac disease, does strict adherence to a gluten-free diet improve leaky gut?

Yes, this should return tight junctions nearly to normal.

Are persons with leaky gut, including those with celiac disease more prone to develop food allergies and sensitivities?
This is possible and reasonable to suggest but has not been proven at this time.

Do the proteins gluten and casein promote the development of leaky gut?
There is no evidence that these proteins promote disease outside of individuals with celiac disease or allergies to these proteins.

If a person has leaky gut should they avoid gluten and casein regardless of whether they have celiac disease or milk allergy?
There is no evidence to avoid these or other proteins unless celiac disease or allergy has been documented.

In addition to celiac disease, what other conditions are associated with leaky gut?
Chronic liver disease, type 1 diabetes, gastrointestinal infections, severe systemic infections, severe burns or trauma, pancreatitis, asthma, diarrhea predominant IBS, crohn’s disease, asthma, rheumatoid arthritis.

What role if any does leaky gut play in autism spectrum disorders?
Leaky gut has been postulated as a predisposing or even causative factor in autism however data on this is minimal and conflicting. I believe a great deal of further research on this subject is necessary before coming to any conclusions.

Thank you Dr. Leffler!

Copyright © by Tricia Thompson, MS, RD

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The truth about leaky gut