Leaky gut is the term used when the protective intestinal barrier becomes damaged and results in large openings developing in the tight junctions of the gut wall. When the integrity of the intestines is compromised, some toxic debris such as partially digested food particles and bacterial fragments may leak through the intestinal walls and lodge in the organs in your body, causing countless biochemical and immunological changes.
Many people with this hidden condition have no idea that they suffer from it, however the leaky gut syndrome, also known as intestinal permeability, is one of the major causes of a wide range of diseases. Research has shown that our health is hugely influenced by the huge population of microorganisms living in our gut and we now have a better understanding on how the gut flora affects our brain, emotions, behaviour as well as physical health - so a healthy gut is vital to one’s health.
Is your gut out of balance?
Basically, your digestive health has a huge impact on your mental and physical health. If you experience any digestive issues, you will lack energy, have poor concentration, and experience frequent headaches, disturbed sleep or unexplained weight gain.
Symptoms of the leaky gut vary from one to another, depending on the extent of the damage to the gut lining. Mild symptoms may include bloating, cramps, gas, indigestion, nausea, diarrhea, dizziness and food intolerances in minor leakage of the gut.
Serious damage of the gut may produce significantly worse symptoms like fatigue, malabsorption, rashes, asthma, irritable bowel syndrome, muscle pain, foggy thinking, low immunity, various infections, and many other autoimmune-related illnesses such as Type 1 diabetes, Grave's Disease, or Crohn's Disease. Many of these autoimmune conditions are strongly associated with intestinal permeability. If you are in doubt, over 10,000 research papers can be found in pubmed.gov on intestinal permeability (or leaky gut) related diseases.
What causes the gut to 'leak'?
Naturopathic doctors and other experts claim the top culprits are non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen which damages the gut or block normal digestive functions, overuse of antibiotics and steroid, as well as processed food, refined sugar, alcohol, and environmental toxins which cause bad bacteria and yeast to grow in the gut and disrupt the delicate ecosystem and friendly gut flora. This leads to overgrowth of bacteria, yeast or parasites in the small intestine, resulting in more serious gut damage, infections and increased intestinal permeability.
Beyond poor diet, many other lifestyle factors such as chronic stress, sleep disturbances, anxiety and even overtraining can cause imbalances of microbiome in the gut. Stress causes lack of blood flow into many organs, suppresses the immune system, alters intestinal physiological function and increases gut permeability; causing inflammation.
I eat healthily. Is leaky gut still a possibility?
It is important to understand that many diseases that seem to be unrelated to the gut such as psoriasis, thyroiditis or arthritis, are actually caused by gut problems. Some people have shown nutritional deficiency or imbalances of body functions, not matter how healthy the food they eat. If you experience any of these symptoms, you need to be aware that your body might not be absorbing nutrients due to impaired digestion and poor gut health.
How does leaky gut occur in the body?
Although most of the symptoms associated with leaky gut occur in the small intestine, your whole digestive system, immune system and nervous system have direct impact on your health.
Mouth: Digestion begins in the mouth. Your first digestive problem will arise if you do not chew your food thoroughly. A proper mechanical breakdown of your food in the mouth helps your stomach to digest it easily.
Stomach: Stomach acids and other enzymes start the breakdown of the food into smaller pieces and move them into the duodenum and small intestines. Stomach acids production decreases as we age, and it's largely affected by chronic stress, excess food intake, alcohol intake or overuse of medication. Incomplete digestion can negatively affect nutrient assimilation and encourage the overgrowth of bad bacteria and yeast. Hence, leaky gut syndrome occurs as a result of low stomach acids and poor digestion; causing gas, bloating and nutrient deficiencies.
Small Intestine: The lining of the intestinal tract has a dynamic and self-renewing population of epithelial cells that participate in several ways to facilitate digestion and absorption. It is a barrier that normally transports the digested micronutrients from the 'inside’ of the gut to the 'outside’ of the gut. Along with frequent ingesting of refined sugar, processed food, medication, chemical, pesticides and food additives, this lining gets battered by poor digestion and assimilation, eventually losing its integrity. Malabsorption and nutrient deficiencies occur when the barrier become dysfunctional. These deficiencies of nutrients will slow down the natural ability of the gut to heal, and cause further damage to the immune system, lymphatic system, liver and other parts of the body where the body has become more vulnerable to infections and attacks its own tissues.
Tight junctions form the seals between the cells of the gut lining, allowing partially digested vital nutrients to pass through the layer, so that they can get into your bloodstream and nourish your body. When these junctions get irritated and inflamed, they loosen up, allowing larger food particles and toxins to sneak into the bloodstream and lymphatic system; triggering food allergies and taxing the immune system. When the immune system is overwhelmed for an extended period of time, leaky gut can develop.
Immune system: On the other side of the intestinal lining, are about two-thirds of your immune system (lymphoid tissues) called Peyer’s patches that live in your gut. They serve as the gatekeeper to your gut.
When toxins and harmful substances come into contact with the linings of a leaky gut, they will be tagged with antibodies that attract white blood cells to neutralise the toxins. This results in the build-up of antibodies which attack not just the food particles but also healthy cells. This type of immune response can cause allergy-type symptoms, and it's also one of the ways many autoimmune disorders develop. Headaches, joint pains, mood swings, fatigue, even skin and vision problems may all arise from an overtaxed immune system and abnormal gut flora environment (also called dysbiosis).
A weakened immune system is prone to various infections as it is unable to block out typical pathogens that multiply in the gut. When toxic bacteria infects the intestinal tract, dysbiosis occurs. Candidiasis is a fungal infection due to a result of yeast (candida) overgrowth during dysbiosis. It is also one of the factors that leads to the changes in the intestinal lining and increases its permeability, resulting in leaky gut. Candida can also produce an aldehyde secretion that shrinks the cells lining the small intestine. This allows intestinal toxins to pass through the tight junctions and enter the tissues and bloodstream, allowing more toxin and chemical absorption, which then affects numerous organs, including the brain. It can escalate into swelling of the lymphatic system, tissue toxicity and inflammation. Eventually, it could lead to a decrease in energy production, muscle and joint aches, foggy brain, anxiety, low body temperature and potentially cancer.
Large Intestines: Your colon has to remove water and waste, especially the toxins produced as byproducts of your metabolism, which your liver dumps into bile. Some beneficial bacteria within the intestines are capable of digesting fibre, making vitamin K, vitamin B12, thiamin and riboflavin, breaking down the bile salts and maintaining pH balance of the intestine, and also metabolise hormones such as estrogen discharged from the liver.
Stress and antibiotics can damage the natural balance of the gut flora in the colon. If you lack these beneficial bacteria to break down the bile salts and estrogen, bile salts will enter freely and damage the colon, contributing to colon cancer; excess estrogens will be reabsorbed and bind to the tissues such as breast, uterus or ovaries, resulting in premenstrual syndrome, fibroids or tumours. You will then become toxic if you have difficult bowel movements, which in turn increases the risk of many chronic and life changing health consequences.
In summary, leaky gut syndrome is a key element in the pathogenesis of many different diseases. Your gut health is the mirror of your total physical health. Hippocrates, the founder of medicine once said, "All Disease Begins In the Gut." Therefore, I believe "True Health Starts In the GUT", too.
Look out for the next article - Leaky gut healing protocol.
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