Leaky Gut Specialist

leaky gut specialist harley street

Guardian featured Harley Street IBS & Autoimmune Clinic is known as the leaky gut specialist. Leaky Gut or Intestinal Hyper-permeability does exist and has been discussed in the medical literature for at least 100 years and there are many health conditions and diseases related to it.

The Greek physician,Hippocrates, known as the Father of Medicine and who lived around 460-370BC, said, “All disease begins in the gut.” It’s over 2,000 years since he died and scientific research has now proven he was right. There is now a growing understanding of immunity, gut function and how  diet and lifestyle can damage our gut.

What Causes Leaky Gut?

The intestines are protected by a single layer of epithelial cells that are linked together by tight junction proteins. Leaky gut is a consequence of intestinal tight-junction malfunction, where the junctions are no longer as tight as they should be. These junctions are in effect a kind of border control that controls what is allowed to pass into the bloodstream from the digestive system. Nutrients are allowed to pass through but anything toxic or disease causing such as bacteria is kept out.

When you have leaky gut, tiny particles that should never be able to enter your bloodstream manage to get through. This results in autoimmune reactions and inflammation.

Some of the underlying causes of leaky gut include:

  • Environmental factors
  • Poor gut flora
  • Poor diet
  • Long-term stress
  • Toxicity

What are some of the symptoms of leaky gut? 

  • Food Sensitivities – because of the toxins that enter the bloodstream, the immune system produces various antibodies, which may make them more susceptible to antigens in certain foods. In studies leaky gut and food allergies have been linked
  • Autoimmune Disease – the key to understanding how leaky gut can cause an autoimmune disease is through the research done on a protein known as zonulin. Zonulin is the modulator of intercellular tight junctions. When the zonulin pathway is disrupted, intestinal and autoimmune, inflammatory disorders can occur

Alteration of the gut barrier seems to facilitate the onset of a variety of health conditions. It is therefore important to improve gut barrier functions.

The good news is that work can be done to diagnose and address the underlying issues causing this increase in permeability, thereby helping to alleviate inappropriate immune responses. Our leaky gut specialist can help you.

If you are interested in this Functional Medicine approach to your health issues, please call our Medical Secretary for an appointment with our leaky gut specialist


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Physiological, pathological, and therapeutic implications of zonulin-mediated intestinal barrier modulation: living life on the edge of the wall. Fasano A. Am J Pathol. 2008 Nov;173(5):1243-52. doi: 10.2353/ajpath.2008.080192. Epub 2008 Oct 2. PMID: 18832585

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Zonulin, a regulator of epithelial and endothelial barrier functions, and its involvement in chronic inflammatory diseases.
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Intestinal permeability and its regulation by zonulin: diagnostic and therapeutic implications.
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Breaking Down Barriers: How Understanding Celiac Disease Pathogenesis Informed the Development of Novel Treatments.
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Restoration of impaired intestinal barrier function by the hydrolysed casein diet contributes to the prevention of type 1 diabetes in the diabetes-prone BioBreeding rat. Visser JT, Lammers K, Hoogendijk A, Boer MW, Brugman S, Beijer-Liefers S, Zandvoort A, Harmsen H, Welling G, Stellaard F, Bos NA, Fasano A, Rozing J. Diabetologia. 2010 Dec;53(12):2621-8. doi: 10.1007/s00125-010-1903-9. Epub 2010 Sep 19. PMID: 20853098 Free PMC article.

Development, validation and implementation of an in vitro model for the study of metabolic and immune function in normal and inflamed human colonic epithelium. Pedersen G. Dan Med J. 2015 Jan;62(1):B4973. PMID: 25557335 Review.

Zonulin as a potential putative biomarker of risk for shared type 1 diabetes and celiac disease autoimmunity. Wood Heickman LK, DeBoer MD, Fasano A. Diabetes Metab Res Rev. 2020 Mar 12:e3309. doi: 10.1002/dmrr.3309. PMID: 32162764 Review.