Mindful EM: What You Need to Know about the Leaky Gut : Emergency Medicine News

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Mindful EM

Mindful EM

What You Need to Know about the Leaky Gut

Hazan, Alberto MD; Haber, Jordana MD

Author Information
doi: 10.1097/01.EEM.0000482480.51203.62
    Never heard of leaky gut syndrome? You're not alone.

    Eating dark chocolate can be an orgasmic experience.

    For some people, the absorption of cocoa flavanols from the gut leads to an immediate surge of serotonin release in the brain, giving rise to feelings of euphoria. The flavanols in dark chocolate have also been linked to improvements in cognition, likely mediated through a combination of angiogenesis and neurogenesis in the hippocampus.

    We know the basic principles of how chemicals from food go from our gut to our brain. A refresher: The small intestine is lined with a layer of epithelial cells that has selective permeability. It absorbs nutrients from food while preventing harmful substances (in the form of antigens) from leaving the GI tract and entering the body. In the case of dark chocolate, epicatechin and other antioxidant molecules in cocoa flavanols cross the blood brain barrier, enter the brain, and go to work.

    Enterocytes prevent harmful substances — like foreign proteins, toxins, large molecules, and microorganisms — from entering the body. Zonulin, a protein at the tight junction between the epithelial cells lining the small intestine, is a big player in deciding what goes into our bodies and what stays in the gut. It selectively opens up the space between enterocytes and allows certain substances to enter the body while keeping others in the gut.

    Host of Disorders

    The leaky gut syndrome postulates that those large protein molecules, microorganisms, and foreign substances enter the bloodstream when there is pathology at the lining of the epithelium of the small intestine, in particular when the space at the tight junction between cells modulated by zonulin is wider than it should be. Antibodies target these antigens that don't belong in the body, and an immune response develops. Leaky gut syndrome proponents believe this immune response leads to a whole host of disorders, including irritable bowel syndrome, Crohn's disease, ulcerative colitis, celiac disease, multiple sclerosis, food allergies and sensitivities, and perhaps some forms of cancer. Detractors, however, say no evidence suggests that the syndrome even exists.

    The tight junction between enterocytes are perpetually opening and closing in response to a plethora of stimuli such as food, hormones, inflammatory markers, and dietary state. Certain microorganisms and proteins can hijack the cellular pathways at these tight junctions or increase the zonulin levels, leading to increased permeability. One of the most powerful triggers is gliadin, a protein found in wheat. Gliadin, like gluten, has been linked to celiac disease. A study from Scandinavia, though, demonstrated that zonulin levels rise after the ingestion of gliadin even in people not affected by celiac disease.

    The concept of intestinal permeability is not controversial. The sugar-absorption test using lactulose and mannitol has been well validated to measure intestinal permeability. It is debatable, however, whether a porous intestine directly leads to human disease. Little scientific evidence currently supports that claim. There is also a dearth of evidence proving the current treatment for a leaky gut, particularly avoiding certain foods and taking nutritional supplements to prevent or cure disease.

    Be Compassionate

    More research needs to be done before we can attribute certain autoimmune disorders and allergies to intestinal permeability, but that doesn't mean we should ignore the topic. We emergency physicians evaluate people with chronic abdominal pain daily. A significant proportion of these patients have had close follow-up with an internist and gastroenterologist. They have had endoscopies and colonoscopies, CT scans and ultrasounds, CMPs, and stool cultures, and still, they have no specific diagnosis and continue to suffer with debilitating abdominal pain, bloating, gas, and food allergies.

    Patients become frustrated after being told their workup is normal. A significant percentage of them are turning to alternative medicine for an answer. Anecdotally, thousands of people have found benefit in following a strict gluten-free diet (even though they tested negative for celiac disease) and in ingesting probiotics and nutritional supplements like glutamine, which is presumed to be the ideal food source for enterocytes.

    We should encourage those patients with a negative workup to continue seeking further treatment and empower them to keep searching for a cure. We should urge them to become experts of their own disease. At the very least, we should be compassionate and listen to them and take their complaints seriously. Many of us have never heard of the leaky gut syndrome. We need to keep in mind that something is happening at the cellular level to account for some of our patients' chronic abdominal pain of which we are not aware. We need to recognize our ignorance. As Donald Kirby, MD, a gastroenterologist and the director of the Center for Human Nutrition at the Cleveland Clinic, stated, “Physicians don't know enough about the gut, which is our biggest immune system organ.”

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