Under healthy conditions, the gut lining or “intestinal mucosa” permits the absorption of vital nutrients from bowel while presenting a barrier against the passage of pathogenic substances into the body.
Leaky gut syndrome or intestinal permeability involves an increase in the permeability of the gut lining. This causes an increased absorption of intestinally derived endotoxins, antigens, inflammatory mediators, and, in some cases, intact bacteria.
An analogy of this is to think of the cells of your intestinal lining as bricks which sit side by side. These “bricks” are held together by proteins that form tight junctions, which can be considered the “mortar” between the bricks. Micronutrients are absorbed into the epithelial cells and transported through the cells and basement membrane where they enter the bloodstream. If the mortar starts to break down, you get penetration of foreign molecules through the intestinal barrier which can then enter the bloodstream (hence the term “leaky gut”). These foreign molecules may include undigested food molecules, toxins or bacteria.
Normally the body sees only tiny food antigens and limited amounts of bacteria. When it sees these new, larger ones, it considers them foreign invaders. Antibodies are then produced against once harmless foods and your immune system becomes increasingly occupied with chores it should not have to be performing. Your health becomes more difficult to maintain as increasing numbers of foods must be avoided for you to feel well.
Even though the gut is becoming leakier, vitamin and mineral absorption becomes reduced – not increased, as you might expect – because some carrier mechanisms of absorption become damaged as part of the process. Many nutrients have to be carried across the barrier and will not otherwise be absorbed.
When the gut becomes leaky or inflamed, the following may occur:
- The gut does not properly absorb nutrients, leading to fatigue and bloating.
- The absorption of large food particles creates new food sensitivities and new symptoms with potential new targets for the storage of antigen antibody complexes such as in the lungs (asthma) or the joints (arthritis).
- Damage to the proteins whose job it is to carry minerals across the gut wall, causing potentially, multiple nutrient deficiencies.
- Damage to or breaching of the gut wall’s detoxification capability, leading to new chemical sensitivities and potential overload of the liver.
- Interference to the gut’s protective coating of immunoglobulins, resulting in decreased defense against bacteria, protozoa, viruses and yeasts.
- Spread of infection due to the ‘escape’ of bacteria and yeast from the intestine.
- Formation of auto-antibodies due to leaking of body tissue look-alike antigens. This means the body can form antibodies to proteins similar or same as human proteins, and then your immune system starts to attack parts of the body leading to autoimmune disease.
Conditions associated with intestinal permeability defects include:
- Auto-immune Disease including Type 1 diabetes, Multiple Sclerosis, Systemic Lupus Erythmatosus, Graves Disease, Hashimotos, Rheumatoid Arthritis
- Inflammatory Bowel Disease including Crohn’s, Celiac Disease and Ulcerative Colitis
- Autism and ADHD
- Chronic Fatigue Syndrome
- Inflammatory Joint Diseases
- Food Allergies and Intolerances
- Atopic Dermatitis, Eczema
- Psychological Conditions including Anxiety, Depression, Schizophrenia
What are the Causes of Intestinal Permeability?
Some of the major causes of leaky gut:
- Diet: Researchers have identified a protein called zonulin that increases intestinal permeability in humans and other animals. Wheat and other gluten-containing grains contain a protein called gliadin, which has been shown to increase zonulin production and thus directly contribute to leaky gut. Similarly dairy contains a powerful glycoprotein called casein, also used to make waterproof adhesives. Casein coats the micro villi (finger like projections off the linin gof the intestinal tract) of the small intestines and keeps them from functioning optimally – at worst damaging and destroying them altogether. Corn and soy also contain powerful glycoproteins which also work to bind and destroy the gut lining.
- Drugs: Prescription antibiotics disrupt the balaace of gut flora by killing both the good and bad bacteria in the gut. Frequent use of NSAIDS (non-steroidal anti-inflammatory drugs such as Advil, Motrin, Aleve) can very often damage the gut lining and suppress adequate production of stomach acid and protective mucous. Alcohol can also damage the seals between cells, allowing water-soluble substances to pass through the gaps and into the bloodstream.
- Xenobiotics or Environmental Toxins: With the detoxification system overloaded or dysfunctional, environment toxins from either inside or outside the body may build up. They can irritate the intestinal lining. The constant inflammation and immune system activity can create a more permeable gut wall.
- Stress: The intestinal lining replaces itself, on the average, every 14 hours. To replace intestinal walls you need blood and the first organ to lose blood during stressful situations is intestinal tract. If you experience a lot of stress, your intestinal lining will not regenerate making intestinal permeability more likely. Chronic stress will also deplete a gastrointestinal tract immune protein known as secretory IgA, which will then allow easier entry for protein molecules into the bloodstream. Cortisol, the body’s key stress hormone, also degrades the gut lining and contributes to leaky gut.
- Infections: Overgrowth of other harmful bacteria, yeast infections, parasitic infections, and intestinal viruses can contribute to a leaky gut. An overgrowth of H. pylori, a bacterium in the stomach, can cause ulcers and leaky gut. The overgrowth of the yeast Candida albicans may contribute to intestinal dysbiosis. When Candida albicans changes from a yeast to fungal form it forms rhizoids, a root like structure, that breaks the intestinal walls. Even when you get Candida in balance and heal the gut, your food allergies will remain for a while because you will still have the antibodies to that food.
- Low Levels of Stomach Acid & Pancreatic Enzymes: Inadequate stomach acid (HCl) and pancreatic digestive enzymes creates difficulties in food digestion leading to inappropriately large proteins and pathogens reaching the small intestines.
- Hormone Imbalances: The gut depends on proper hormone levels for good health. When estrogen, progesterone, testosterone, or thyroid hormones are deficient or out of balance, this imbalance can contribute to leaky gut.
- Low Zinc Levels: Zinc is necessary in maintaining intestinal wall integrity. Zinc is often deficient in many individuals as it is also used to synthesis serotonin, the body’s key calming neurotransmitter so is depleted by high levels of stress. The standard Western diet is also deficient in rich sources of zinc.
Symptoms of Intestinal Permeability include:
- Digestive issues such as gas, bloating, diarrhea or irritable bowel syndrome (IBS).
- Food allergies or food intolerances.
- Fluid retention and weight gain.
- Seasonal allergies, sinus issues or asthma.
- Hormonal imbalances such as PMS or PCOS.
- Diagnosis of an autoimmune disease such as rheumatoid arthritis, Hashimoto’s thyroiditis, lupus, psoriasis, or celiac disease.
- Joint pain and inflammation
- Diagnosis of chronic fatigue or fibromyalgia.
- Mood and mind issues such as depression, anxiety, ADD or ADHD.
- Skin issues such as acne, rosacea, or eczema.
- Diagnosis of Candida albicans overgrowth.