Leaky Gut

So many people to-day have problems with their digestive system, either indigestion, heartburn, or bloating.

If we proceed lower down the digestive track we can see many problems arising in our intestine, or our ‘gut’ as many people refer. Think of your gut as a one-way fence.   The lining of the gut is permeable, that is, small particles of food are able to pass through it into the other cells of our body – but in a healthy body, these ‘holes’ are small enough to keep in contained molecules which might otherwise cause harm. Beside containing the nutrients we need and which will pass through our permeable gut, food contains a toxic load the body needs to be protected from.  This protection is supplied by complex mechanisms which support one another; intestinal secretions and certain white blood cells.   It is thought that this complex system that the digested, important portions of food are able to pass through to the body, while toxins are barricaded out.

This intestinal barrier is supported by the liver through which all food substances must pass before entering our circulatory system to be carried to other tissues and organs. Certain cells in the liver remove absorbed molecules which are too large to pass through the gut.   Liver enzymes also transform certain chemicals produced in the gut by the oxidation and with such substances as the amino acid glutathione (GSH) for excretion into bile and for circulation to the kidneys.

Nevertheless the cost of this detoxification is high; free radicals are generated, and antioxidants like GSH are contained in large quantities. Whenever this intestinal barrier is damaged in any way, the number of free radicals and carcinogens in the liver’s oxidase system are increased. In fact this sort of toxic overload where extra ‘toxic’  bile is produced and backs up into the pancreatic ducts, may be the major cause of chronic pancreatic disease (Lancet, 1983; ii:375-8).

A damaged intestinal barrier function can also cause disease directly. Whenever this natural permeability of the gut is increased, it stimulates allergic type responses to foods and components of normal gut flora.

Leaky gut syndrome is one of a number of disorders associated with increased intestinal permeability, where the one-way gates of the gut, in effect open too wide.  A number of conditions have been shown to be accompanied by a leaky gut.  These include inflammatory and infectious bowel diseases, chronic inflammatory joint diseases, skin conditions like acne, psoriasis and dermatitis and many diseases triggered by food allergy or specific food intolerance, including eczema, urticaria and irritable bowel syndrome and chronic fatigue syndrome and even chronic hepatitis. Increased gut permeability  may play a primary role in causing these diseases or it may be a consequence of it, but by causing immune system reaction, liver dysfunction and pancreatic insufficiency, it creates a vicious cycle.  In most cases, the role of increased intestinal permeability in these sorts of patients often goes unrecognized.

Causes of Leaky Gut

A leaky gut is caused by exposure to substances which damage the lining of the intestine.   The commonest causes of damage are infectious agents ( viral bacterial and protozoan, alcohol and non steroidal anti-inflammatory drugs.  Other causes include hypoxia (too little oxygen) of the bowel such as occurs during open heart surgery or shock (Ann Thorac Surg. 1993;55:1080-6) and chemotherapy drugs.   Whatever causes leaky gut once the condition has developed it can be self perpetuating.


The relationship between food sensitivities and the leaky gut is complex and circular. In experimental trials, children and adults with eczema, urticaria or asthma triggered by food allergy show that they have higher gut permeability than those who don’t have these conditions. (Allergy, 1989; 9:47-51). This may indicate that allergies and food sensitivities may by increased by aleaky gut.   But by the same token, whenever allergic subjects are exposed to allergenic foods, gut permeability sharply increases.  What this probably means is that an increase in intestinal permeability is both important as a cause of food allergy and also the result of food allergy.


Nutrients are ordinarily absorbed through the cells.  If the lining of the gut is damaged, this absorption decreases, possibly causing malnutrition which only makes other problems worse.  Under normal conditions the lining of the intestine has the fastest production of new cells of any tissue in the body, old cells slough and a new lining is generated every three to six days.  That is why it is important for the metabolic demands of this normally rapid cell turnover to be met if a damaged gut lining is to be able to heal.  If they aren’t the gut becomes even more permeable and you become even more nourished.

Bacterial Dysfunction

A kind of low-level dysfunction, called dysbosis, is caused by ordinarily unviulent organisms which mainly do their damage by altering the metabolic or immune responses of the body.   The situation when the immune system begins to react and destroy normal gut flora is one example that has been implicated in the development of conditions such as Crohn’s disease and ankylosing spondylitis.  Recent research suggests that this kind of gut bacterial sensitization is an early complication of altered permeability. This phenomenon is a well known and studied side effect of non-steroidal anti-inflammatory drugs (NSAIDs).  Single doses of aspirin or indomethacin increases cellular permeability in part by inhibiting the synthesis of the protective fatty acid prostaglandins. Long term anti-inflammatory drugs leaves the intestine highly inflamed.  Changing the flora of the gut through the use of antibiotics, synthetic and natural, probiotics such as acidophilus (the friendly bacteria) and diet is one strategy for breaking the vicious cycle in leaky gut syndrome.

Stress on the Liver

The liver of the leaky gut patient works overtime to remove oversized food molecules and to oxidize gut toxins, causing increased production of free radicals.  This in turn causes damage to liver cells and sends by-products into the bile duct, therefore producing a toxic bile capable of damaging bile ducts and backing up into the pancreas.  (Lancet, 1983; ii:375-8). In attempting to rectify all this the liver depletes its reserves of certain amino acids.  We know that this happens in liver diseases caused by alcohol.

  • A Leaky gut can cause such symptoms as
  • Fatigue and malaise
  • Arthralgias (joint pain)
  • Myalgias (muscle pain)
  • Fevers of unknown origin
  • Food intolerances
  • Abdominal pain
  • Abdominal distension
  • Diarrhea
  • Skin rashes
  • Toxic feelings
  • Cognitive and memory deficits
  • Shortness of breath
  • Poor exercise tolerance

How to Heal a Leaky Gut

It is possible to cure a leaky gut with a nutrient-dense diet and appropriate supplements.  Many natural substances help repair the intestinal mucosal surface or support the liver when stressed by toxins. Your vitamin and mineral supplements should include all the B vitamins, vitamin A ,C,and E, zinc selenium manganese and magnesium.   Because of the association between increased gut permeability and pancreatic dysfunction, pancreatic enzymes may also be needed.

  • Avoid drugs which damage the gut.
  • If you haven’t discovered all your allergies, follow a highly nutritious elimination diet, tailor made for you.

The following substances can repair the gut wall:
Epidermal growth factor (EGF), a polypeptide that stimulates growth and repair of the epithelial tissue, is widely distributed in the body with high concentrations detectable in saliva.

Chew your food thoroughly to increase salivary EGF.  Purified EGF has been shown to heal ulceration of the small intestine (Lancet,1993;341::843-8).

Saccharomyces boulardii, a non-pathogenic yeast originally isolated from the surface of lichee nuts, has been widely used in Europe to treat diarrhea.  In France it is popularly called “yeast against yeast” and is thought to help clean the skin in addition to the gut.

Lactobacillus caseii var GG, a strain of lactobacillus isolated and purified in Finland, has been shown effective in the prevention of diarrhea and in the treatment of colitis.  It also improves the gut permeability associated with rotavirus (Ann Med,19990; 22: 57-9).  Although the ability of other lactobacillus preparations to improve leaky gut has not been directly tested, it is suggested by the ability of live cultures of L. acidophilus to diminish radiation-induced diarrhea, a condition directly produced by the loss of mucosal integrity.

Glutamine, the amino acid needed for the maintenance of intestinal metabolism, structure and function has been shown to reverse all the gut abnormalities in patients fed intravenously.  Glutamine also repairs gut-lining damage caused by chemotherapy or radiation (Arch Surg. 1990; 125:1040-50).

Glutathione (GSH) is an important antioxidant.   Lowered levels of liver glutathione is a common occurrence in leaky gut syndromes, contributing to liver dysfunction and liver necrosis among alcoholics and immune impairment in patients with AIDS.  The most effective way to raise liver glutathione is to take its dietary precursors, systeine or methionine;  the best supplements for leaky gut are GSH and N-acetyl systeine.

Take flavonoids before eating.  They may block allergic reactions which increase permeability.  Catechins have been used in Europe to treat gastric ulcerations; the flavonoids in milk thistle (silymarin) and in dandelion root, can protect the liver.

Take essential fatty acids (EFA’s) particularly gamma-linolenic acid (GLA).  In laboratory experiments, fish oil was able to prevent intestinal mucoal injury produced by methotrexate and protect the body from the toxins produced in the gut .  Take these in their most concentrated and physiologically active form to avoid exposure to large quantities of polyunsaturated fatty acids.

If you are supplementing with dietary fibre,make sure you are taking hypoallergenic insoluble fibre, and watch the amount.  Too much may increase gut permeability (J Nutr,1983;113:2300-7).

Gamma oryzanol, derived from rice bran has been extensively researched in Japan for its healing effects in the treatment of gastric and duodenal ulcers and potent antioxidant activity (Rep Hokaido Inst Pub Health, 1966;16:111)