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Dr Sharma Diagnostics

Leaky Gut Syndrome

A brief overview of leaky gut or intestinal permeability

The small intestine acts like a selective sieve. Only the breakdown products of digestion such as, vitamins, minerals, small-chain fatty acids, amino acids and short protein chains called peptides should pass into the blood stream. Larger proteins, carbohydrates and fats are kept out.

If the integrity of the bowel wall is compromised, then larger molecules may pass from the intestine into the blood stream. This is known as increased intestinal permeability. Once in the blood stream, they may be recognised as foreign particles, triggering an immune response which can occur with or without inflammation and with no symptoms.

If the situation is not treated, the body may continue to respond to some foods as if they are organisms such as bacteria or viruses, creating a chronic immune response or allergic reaction. If a particle has the same structure as cells in our body, a process known as ‘molecular mimicry’ can occur. Here the immune system ends up attacking our cells creating autoimmunity.

The bowel has 30 -100 trillion bacteria in it and 10 times that number of viruses. There are also colonies of yeasts, fungi and often parasites. These too may also pass into the blood stream risking infection and the development of sensitivity to ‘friendly’ bacteria.

This has the potential to cause or exacerbate a range of symptoms and physical conditions including food allergy, auto-immune diseases such as inflammatory bowel disease, certain arthritic issues, and skin problems, autoimmune disease, migraine, hay fever and asthma. There are theoretical connections to neurological & mental problems such as MS, depression and even autism and schizophrenia.

What might cause a leaky gut?

Anything that irritates, damages, or inflames the bowel wall can cause a leaky gut. This can include parasitic, fungal, bacterial, or viral infection. More commonly, the syndrome is caused by something that diminishes the bowel’s natural flora.

These ‘good’ bacteria in the healthy gut help the body to digest food and utilise vitamins and minerals and, very importantly, kill off bad bugs as well as lining the bowel wall as a protective layer. Their numbers may fall when one takes antibiotics (either prescribed or found inadvertently in processed foods) and through the ingestion of pesticides, preservatives, additives and environmental chemicals and metals.

Food allergy or intolerance may be associated with a lack of stomach acid and pancreatic enzymes which allows undigested foods to reach the part of the small intestine involved with absorption. These larger molecules of undigested food may enter the blood stream and trigger immune reactions.

Stress may also play a role. Stress can trigger an acidic response from the stomach altering the bowel pH levels preventing digestion. An increase in adrenaline reduces blood flow to the bowel, reducing the supply of oxygen and nutrients so that the bowel wall is not well nourished. Stress may also reduce the pancreatic enzyme production.

Diagnosing Leaky Gut

The choice of which test is best is made based on each individual case. Specific laboratories offer a range of tests.

  1. PEG Test for Increased Intestinal Permeability.
    The simplest test to perform is a urine test. A solution of inert (indigestible and poorly absorbed) Polyethylene glycol molecules of different sizes (PEG 400 – not one associated with vaccines and not known to have any risks) is drunk and the urine is then collected for the following 6 hours. A portion of the collected urine is sent to the laboratory, with a record of the amount of urine passed in that time. This is analysed for the presence of PEG of which very little will be found in a non-leaky gut.

    Inflammation may block the absorption, so the sensitivity of the test is possibly less than that of the blood tests.

  2. The Advanced Intestinal Barrier Assessment (Blood test). This test measures 7 markers that in combination provide an indication of a leaky gut as well as possible underlying cause.

    • Zonulin. This is a compound that is released by the intestinal wall lining to expand so-called ‘tight junctions’ which allow larger molecules required by the body to pass through into the bloodstream. A higher-than-expected level would cause a ‘leaky gut’. This test is not highly specific as Zonulin can also be increased in an inflamed gut from other causes - smoking, alcohol abuse, certain infections & diseases, gluten sensitivity and by some medications – but if high increased intestinal permeability is likely.

    • Histamine. Mast Cells release histamine in response to food to which one is allergic, and histamine is also found in many foods, some contain very high levels, which can then trigger allergic response.

    • Diamine Oxidase. This is an enzyme that breaks down histamine. It is often found to be deficient in those who overreact to foods.

    • Lipopolysaccharide (LPS) binding-protein. The test identifies defence molecules called immunoglobulins that react to LPS protein which is found in the coat of particular bacteria that are associated with the presence of the leaky gut.

    • An example report can be seen here:

  3. An alternative measurement can be made through a stool (faecal) test measuring Zonulin. This test is generally only recommended by Dr Sharma if a comprehensive digestive stool analysis is also being undertaken as Zonulin many rise for reasons other than increased intestinal permeability.

Test costs

The cost of tests is inclusive of postal/courier charges, admin and the phlebotomy for the blood test if done by one of the nursing services used by Dr Sharma.

The charges also include Dr Sharma’s individualised result summary.
  1. PEG urinalysis testing (less informative than the other tests as it does not give an indication of other issues) Cost £210.
  2. The Advanced Intestinal Barrier Assessment is the most extensive of tests providing information not only on permeability but also on food intolerance/allergy and potential infection often linked with leaky gut. Cost £457
  3. The faecal test (less specific but sensitive) is £100 when bolted on to the Comprehensive Digestive Stool analysis (£435).

Dr Sharma’s practice can arrange for a test kit to be sent to you (we’ll ensure the correct laboratories are used as the accuracy of internet tests cannot be guaranteed) and you can arrange through the practice to come to a clinic for the blood test or have the blood taken local to your home.


Dr Sharma’s report will discuss the results and options for a naturopathic treatment protocol. These may include:
  • Dietary advice
  • Probiotics (to replenish bowel bacteria and challenge yeast or candida infection) with nutrients to sooth bowel inflammation.
  • Plant extracts acting as antibacterial/yeast/parasitic agent.
  • Plant extracts and nutrients to heal inflamed or damaged bowel wall.
  • The antioxidant L-glutathione (known to increase the integrity of gut lining cells) and essential for bowel membrane integrity

Dr Sharma takes an integrated approach so any treatment programme will be carefully personalised to you and combined with lifestyle advice.

Additional Points of Possible Interest

Rheumatoid Arthritis A study in the British Journal of Nutrition British Journal of Nutrition British Journal of Nutrition / Volume83 / Issue03 / March 2000, pp 207-217 drew a connection between rheumatoid arthritis and a leaky gut

Multiple sclerosis. The New England Journal of Medicine (Albert L J and Inman RD, 2000;341(27):2068-2074) has published a review article supporting the possibility of increased intestinal permeability having an associations with multiple sclerosis. They suggest MS might be associated with the immune system recognising protein sequences in foreign substances which actually resemble the body’s own nerve proteins thereby causing an attack on the nervous system. This has been termed molecular mimicry.

Inflammatory Responses in many conditions. Another paper suggests intestinal hyperpermeability (a medical term for “leaky gut”) is implicated “ diseases such as systemic inflammatory response syndrome (SIRS), inflammatory bowel disease, type 1 diabetes, allergies, asthma, and autism” It concludes by saying “ A better basic understanding of this structure might lead to prevention or treatment of these diseases using nutritional or other means” ( Z Liu1, N Li2, J Neu2,* Acta Paediatrica Volume 94, Issue 4 , pages 386–393, April 2005)

Autoimmune disease
For those with autoimmune issues, please read through the information on this link below which will explain fully about the condition and provide you with some diet advice and tips.

Medical Disclaimer

The information is given as advice not as a prescription. Should you wish to consider any level of treatment you are strongly advised to discuss your case and/or results with a Functional Medicine trained Doctor, a nutritionist, or even your GP.

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