Many autoimmune diseases are compounded by the presence of leaky gut. By identifying and removing the cause of leaky gut, the immune system may become more balanced.
What is leaky gut?
Certain autoimmune diseases can be linked to excessive stimulation of the immune system due to increased intestinal permeability, or leaky gut, as this phenomenon is often termed.1 In normal intestinal function, food particles are broken down into the simplest pieces, which are absorbed into the bloodstream. Normally, the immune system tolerates these smaller “building blocks” of foods entering the bloodstream without issue. However, when leaky gut is present, larger food proteins are allowed to enter the bloodstream. This is stimulatory to the immune system. Recent research has pointed to overstimulation of the immune system as a trigger for autoimmune reactions 2, and these larger food “particles” entering the bloodstream can certainly be a contributor to this overstimulation. In addition, increased permeability of the intestine also allows bacterial particles and toxins to enter the bloodstream, further irritating the immune system and burdening the liver.
How is leaky gut diagnosed?
One way to test for leaky gut is to perform a lactulose-mannitol test. A number of labs commonly utilized by naturopathic physicians will perform this test. One method of collection involves an overnight fast, followed by a morning urine collection. The patient will then consume a drink composed of a lactulose/mannitol solution. The patient will then collect urine samples for a number of hours after drinking the solution to assess the level of leaky gut.
What Causes leaky gut?
A number of factors can contribute to leaky gut. First, an imbalance of the gut bacteria can alter the normal intestinal barrier.3 Normally, the probiotic bacteria in the gut maintain a healthy intestinal barrier, but the barrier becomes dysfunctional as probiotic flora status changes.4 Second, the use of nonsteroidal anti-inflammatory drugs (NSAIDs) can actually contribute to an increase in leaky gut.5 Unfortunately, many patients with autoimmune diseases take NSAIDs for pain relief, and they remain unaware that these medications are worsening leaky gut. Next, presence of bacterial endotoxins can induce injury to the intestinal barrier and contribute to leaky gut.6 The presence of other types of infections, such as Candida yeast, may also contribute. Stress also appears to worsen leaky gut by a number of different mechanisms. 7 One mechanism is by reducing the local immune response in the gut and, therefore, inhibiting the body’s ability to fight off local infections.8 Ingestion of toxic chemicals, including certain pesticides, may also contribute. A recent article found leaky gut in rats exposed to a chemical found in pesticides.9 Diet also plays a role in leaky gut. Research has pointed to increased markers of leaky gut in those with non-celiac gluten sensitivity after the ingestion of gluten-containing foods.10 Other foods may contribute, as well, though more research is needed in this area. IgG antibodies to foods may contribute.11
How is leaky gut treated?
The key to reversing leaky gut is to remove the offending agent. If the cause of leaky gut is determined to be dysbiosis, bacterial infection, stress, or the effect of a food, then it is wise to remove the cause. Repairing the damage to the intestinal tissue can be accomplished through supplementation. First, the amino acid L-glutamine has been proven to be effective for reducing leaky gut.12 Vitamin D has been studied to improve leaky gut, as well.13 Additional strategies include replacing the probiotic flora after performing an analysis of probiotic levels in the stool, along with using antibacterial or antifungal botanicals to remove persistent infections. If stress appears to be the cause, nervine botanicals, such as Passiflora incarnata, may help to reduce stress. Adaptogenic botanicals may help balance cortisol levels and prevent stress-induced gastrointestinal dysfunction. If the patient is abusing NSAID drugs due to pain, utilizing anti-inflammatory botanicals, like Boswellia or Curcuma, may indirectly help reduce intestinal permeability. Promoting a clean, organic diet with a possible gluten elimination may also help restore intestinal barrier function.
Kimberly Sanders, ND, is Clinical Assistant Professor at the University of Bridgeport College of Naturopathic Medicine. She is the founder and chief naturopathic physician of ArthroWell Naturopathic, a private autoimmune speciality clinic in Milford, Connecticut.
References:
- Morris G, Berk M, Carvalho AF, Caso JR, Sanz Y, Maes M. The role of microbiota and intestinal permeability in the pathophysiology of autoimmune and neuroimmune processes with an emphasis on Inflammatory Bowel Disease Type 1 Diabetes and Chronic Fatigue Syndrome. Curr Pharm Des. 2016 [epub ahead of print].
- Tsumiyama K, Miyazaki Y, Shiozawa S. Self-organized criticality theory of autoimmunity. PLoS ONE. 2009;4(12):e8382.
- Morris G, Berk M, Carvalho AF, Caso JR, Sanz Y, Maes M. The role of microbiota and intestinal permeability in the pathophysiology of autoimmune and neuroimmune processes with an emphasis on Inflammatory Bowel Disease Type 1 Diabetes and Chronic Fatigue Syndrome. Curr Pharm Des. 2016 [epub ahead of print].
- González-castro AM, Martínez C, Salvo-romero E, et al. Mucosal pathobiology and molecular signature of epithelial barrier dysfunction in the small intestine in Irritable Bowel Syndrome. J Gastroenterol Hepatol. 2016 [epub ahead of print].
- Gnauck A, Lentle RG, Kruger MC. Aspirin-induced increase in intestinal paracellular permeability does not affect the levels of LPS in venous blood of healthy women. Innate Immun. 2015;21(5):537-45.
- Bein A, Zilbershtein A, Golosovsky M, Davidov D, Schwartz B. LPS induces hyper-permeability of intestinal epithelial cells. J Cell Physiol. 2016 [epub ahead of print].
- Brzozowski B, Mazur-bialy A, Pajdo R, et al. Mechanisms by which Stress Affects the Experimental and Clinical Inflammatory Bowel Disease (IBD). Role of Brain-Gut Axis. Curr Neuropharmacol. 2016 [epub ahead of print].
- Campos-rodríguez R, Godínez-victoria M, Abarca-rojano E, et al. Stress modulates intestinal secretory immunoglobulin A. Front Integr Neurosci. 2013;7:86.
- Joly condette C, Khorsi-cauet H, Morlière P, et al. Increased gut permeability and bacterial translocation after chronic chlorpyrifos exposure in rats. PLoS ONE. 2014;9(7):e102217.
- Hollon J, Puppa EL, Greenwald B, Goldberg E, Guerrerio A, Fasano A. Effect of gliadin on permeability of intestinal biopsy explants from celiac disease patients and patients with non-celiac gluten sensitivity. Nutrients. 2015;7(3):1565-76.
- Karakuła-juchnowicz H, Szachta P, Opolska A, et al. The role of IgG hypersensitivity in the pathogenesis and therapy of depressive disorders. Nutr Neurosci. 2014 [epub ahead of print].
- Benjamin J, Makharia G, Ahuja V, et al. Glutamine and whey protein improve intestinal permeability and morphology in patients with Crohn’s disease: a randomized controlled trial. Dig Dis Sci. 2012;57(4):1000-12.
- Raftery T, Martineau AR, Greiller CL, et al. Effects of vitamin D supplementation on intestinal permeability, cathelicidin and disease markers in Crohn’s disease: Results from a randomised double-blind placebo-controlled study. United European Gastroenterol J. 2015;3(3):294-302.