10 Surprising Health Problems Caused by Leaky Gut
- Everyone recognizes that gas, bloating and diarrhea can come from issues in the gut. But what about eczema, joint pain, rashes, headaches and difficulty losing weight? Yes, those too can be caused by GI problems.
- Eighty percent of the immune system is clustered around the intestines. When people repeatedly consume food that causes an immune activation in the gut, it creates intestinal irritation and lead to leaky gut.
- Understanding more about this insidious condition can help you recognize and finally get the help you need to fix it.
by Dr. John Neustadt
Coiled up in each of us is approximately 30 feet of intestines. This tube is technically outside of our bodies, and for us to be able to use the nutrients we eat our GI tract must be able to digest and absorb them. Everyday we consume all types of food and drinks, but rarely do most people think about what happens after they swallow. Until something goes wrong.
Everyone’s familiar with what happens when we get food poisoning. It’s not fun and it ain’t pretty. Diarrhea, nausea, gas, bloating or cramping are common and easily recognizable. People typically can connect how they’re feeling with what they ate at a recent meal.
But a more chronic and insidious situation not caused by an acute infection is leaky gut, also called hypermeable gut. This condition can create seemingly unrelated symptoms throughout the body. And even if you’re eating the healthiest diet in the world, you may not be digesting and absorbing the nutrients properly, leading to activation of the immune system, nutritional deficiencies and symptoms that most people won’t even recognize as having their root cause in the gut.
Symptoms that can be caused by leaky gut include experiences people typically associate with GI problems: gas, bloating, abdominal cramping. But most people don’t realize that guy dysfunction can also be creating:
- Migratory joint pain (pain that moves around)
- Migratory rashes (rashes that move around)
- Decreased ability to concentrate or process information
- Chronic fatigue
- Sugar cravings
- Autoimmune diseases
- Nutritional deficiencies
- Diarrhea or constipation
There are three major reasons why people develop leaky gut. Someone’s digestion may not be functioning properly; they may have food intolerances that cause chronic immune activation in the gut; or they may have chronic intestinal bacterial or fungal infections, called intestinal dysbiosis. Each of these situations can occur individually or together, and all result in putting one at risk for decreased ability to absorb nutrients, intestinal damage and leaky gut.
Digestion involves the breakdown of large molecules into smaller, readily absorbed molecules. While some digestion begins with the production of enzymes in the mouth, the stomach is where the process of digestion really gets underway. Cells in the stomach excrete specific enzymes to break apart fats, starches, and proteins. The enzymes, however, are inactive and must be activated by stomach acid. When someone produces enough stomach acid, proper digestion in the stomach occurs. But many people don’t produce enough stomach acid. Low stomach acid production is called hypochlorhydria, and when no stomach acid is produced it’s called achlorhydria. Decreased stomach acid production occurs from aging, caffeine, overeating, stress, medications (especially those that block the production or excretion of stomach acid such as Protonix, Tagamet, Pepcid, Axid, Zantac, Prevacid, Prilosec, Aciphex, Nexium), alcohol, and stomach surgeries that destroy the acid-producing cells.
Many people produce less stomach acid as they age, and it’s been estimated that 10–21% of people sixty to sixty-nine years old, 31% of those seventy to seventy-nine years old, and 37% of those above the age of eighty have hypochlorhydria or achlorhydria, and this rate may be higher in people with autoimmune conditions. One question posed to patients to screen for their risk of low stomach acid is, “Do you feel fuller sooner than you used to and stay full longer than you used to when you eat?” If the answer is yes, it may be that they have low stomach acid since decreased stomach acid increases the amount of time food sits in the stomach before passing into the small intestines. When stomach acid is low, vitamins and minerals may not be efficiently released from the food that contains them. This may result in decreased availability of nutrients for absorption and nutritional deficiencies. People with low stomach acid have been shown to be at increased risk for vitamin and mineral deficiencies. Symptoms of low stomach acid production include bloating or distension after eating, diarrhea or constipation, flatulence after a meal, hair loss in women, heartburn, indigestion, malaise, and prolonged sense of fullness after eating. Additionally, the risk of hip fracture increases by 22% after one year and nearly 60% after four years in people taking acid-blocking medications as compared to people not taking them.
Stomach acid plays two other important roles. It acts to sterilize food and signals the lower esophageal sphincter (the muscle separating the esophagus from the stomach) to close. The gut normally contains about four hundred different species of bacteria, which are required for normal digestion and absorption of nutrients. It has been estimated that there are more bacterial cells in the gut than all the cells in the body combined. These beneficial bacteria are required for normal digestion and absorption of nutrients. When inadequate sterilization of food occurs, however, pathogenic (bad) bacteria, viruses, and fungi can pass into the small intestines. This disrupts the healthy ecology in the gut and alters the delicate balance between healthy and unhealthy microbes. This imbalance in intestinal flora is called dysbiosis, and it can occur with the overgrowth of pathogenic bacteria and/or fungus. Symptoms of intestinal dysbiosis include abdominal gas and bloating, post-nasal drip, “brain fog” (feeling like you’re just not mentally sharp), and sugar cravings. Abdominal gas and bloating are caused by fermentation of food by the bacteria and fungus, which causes the production of gas, such as methane. Post-nasal drip is caused by immune system activation by bacteria and fungi. Sugar is the preferred energy source for the fungi, which can lead to sugar cravings. Bacteria and fungi secrete their own waste products, such as ammonia, that can enter the blood stream, cross into the brain, and cause brain fog. Additionally, intestinal bacterial overgrowth is now understood to be a risk factor for developing gastroesophageal reflux disorder (GERD).
A simple urine test can detect acids secreted by pathogenic intestinal bacteria and fungi. These acids enter the blood stream, are filtered by the kidneys, and excreted in the urine. They include d-arabinitol, p-hydroxybenzoate, indican, tricarballylate and dihydroxyphenylpropionate.
When low stomach acid production decreases the ability of the lower esophageal sphincter to close, the result is that the acid produced in the stomach can reflux up into the esophagus and cause symptoms of GERD. The typical medical response to gastric reflux, which can cause burning, coughing, and asthma-like symptoms, is to prescribe acid-blocking medications. However, the actual cause in many people is too little acid and not too much acid. Decreased acid production can occur as a result of decreased histidine, an amino acid that is required for acid secretion. This amino acid is tested as part of an amino acid blood panel, which may diagnose the underlying cause in some patients. Stomach acid production can also be tested by using a meter, called a Heidelburg pH capsule test. Providing histidine to people with low stomach acid can improve their stomach acid production. Low stomach acid can also occur in from infections, such as Helicobacter pylori (H. pylori) in the stomach. Additionally, when people have low stomach acid production, some doctors provide hydrochloric acid capsules for people to take with meals that help improve their digestion and eliminate GERD. There are some instances when people should not supplement with acid pills; therefore, people should only do so after consulting their healthcare provider.
Food intolerances can also cause decreased absorption of nutrients by creating chronic inflammation in the intestines. Eighty percent of the immune system is clustered around the intestines. When people repeatedly consume food that causes an immune activation in the gut, it creates intestinal irritation. Over time, the cells lining the intestines become damaged. This can create malabsorption with decreased ability to assimilate nutrients from food. An extreme example of this is Celiac disease. Intolerance to wheat, rye, barley, and oats characterizes this disease. The immune system actually reacts to gluten contained in these foods. This causes intestinal inflammation and destruction of the cells lining the intestines. Celiac disease has wide-ranging symptoms, including fatigue, anemia, joint pains, depression, loss of balance, and malnutrition.
More frequently, people will react to foods that they crave, such as milk and eggs, which can be detected through a special blood test. This blood test is called an IgG food intolerance test, and people with rheumatoid arthritis, eczema, and other conditions have been shown to have elevated IgG antibodies to foods. IgG is a protein produced by the immune system. Most doctors only test for IgE-mediated allergies, which are also called “immediate hypersensitivity reactions.” An IgE-mediated-immune response is responsible for the life-threatening reaction in some people to bee stings or peanuts. IgG, on the other hand, is a delayed-type-hypersensitivity reaction that, as the name implies, is not immediately apparent. People who test negative on an IgE test can be positive on an IgG test.
IgG reactions may take hours or days to appear, and symptoms can include post-nasal drip, gas and bloating, difficulty losing weight, joint aches, eczema, fatigue, and others. Food intolerances can cause these diverse symptoms for various reasons. Similar to bacterial and fungal dysbiosis, the immune-system activation caused by food intolerances can cause post-nasal drip. Gas and bloating is a result of incomplete digestion of food and the resultant fermentation of these food particles by bacteria in the intestines. Difficulty losing weight may result from an increased cortisol response by the body due to the continual stress placed on the immune system. When cortisol is chronically elevated, it causes an accumulation of abdominal fat.
The explanation for eczema and joint pains is a little more complicated. When the immune system in the intestines is activated, the antibody-antigen complexes enter the blood stream. An antibody is the protein produced by the immune system such as IgG, and an antigen is the molecule against which the immune system is reacting, such as a protein in milk. These antibody-antigen complexes travel from the intestines to the liver where they are broken down for elimination by the body. This process is like a conveyor belt where the antibody-antigen complexes are delivered to the liver for processing, but the amount of complexes delivered to the liver over time can overwhelm the liver’s ability to detoxify them. When this occurs, the complexes pass through the liver and enter the systemic circulation. Like bits of sand in a river, these complexes can settle out of the blood stream where the flow of blood slows down. This occurs in the skin and joints. When these complexes are deposited in skin and joints, they act as irritants that can create local immune-system activation and produce such symptoms as joint pains and eczema. Frequently, the joint pains will be migratory, meaning different joints will be affected at different times.
Chronic stress predisposes people to low stomach acid production and food intolerances. This is because stress stimulates the release of cortisol, norepinephrine, and epinephrine. These are part of the flight or flight response to stress. The analogy that’s often used to teach this concept to medical student is, “Imagine that you’re being chased by a tiger.” The body has two responses. It either flees or battles it out. In either case, cortisol and epinephrine are secreted to prepare people for action. They increase blood flow to skeletal muscles and decrease it to the intestines. These hormones also increase heart rate and alter blood flow in the brain. By shifting blood flow away from the intestines and to the muscles, digestion decreases. This can also cause damage to the cells lining the intestines and create a “hyperpermeable gut.” When digestion decreases, it allows larger food particles to enter the small intestines where food is absorbed through the lining of the gut and into the body. The larger food particles, combined with the damaged lining of the gut, can activate the immune system and create food intolerances.
The fight or flight response is part of the sympathetic nervous system. Balancing the sympathetic arm of the nervous system is the parasympathetic nervous system. In contrast to the fight or flight response, the parasympathetic nervous system is referred to as the rest and digest response. If people slow down when they eat, and eat in a relaxed fashion, the sympathetic nervous system decreases activity and the parasympathetic nervous system increases activity. When this occurs, blood flows to the intestines for improved digestion and assimilation of nutrients. Taking time for relaxation is imperative for proper body function. Relaxation is vital for promoting health, and many people do not take any time out for this during their busy weeks.
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