The 1 Missing Underlying Cause of Irritable Bowel Syndrome(IBS)

The 1 Missing Underlying Cause of Irritable Bowel Syndrome(IBS)
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Small intestine bacterial overgrowth, also known as SIBO, is excessive bacterial overgrowth in the small intestine, also referred to as, the small bowel.

  • SIBO is a digestive disorder that is becoming more prevalent and occurs in many individuals who have Irritable Bowel Syndrome (IBS).
  • Bacteria exist throughout the entire digestive tract. The small intestine has low levels of bacteria and the large intestine, the colon, has the highest colonization of bacteria.
  • The problem arises when bacteria invades and colonizes the small intestine causing an overgrowth and imbalance of gut bacteria.

This overgrowth of bacteria leads to gut dysbiosis, impaired nutrient absorption, damage to the gut lining, and similar symptoms to IBS- gas, bloating, and pain.

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In a well-balanced gut microbiome, the colon has the highest concentration of bacteria, which helps the body digest food and absorb nutrients. The small intestine has the least bacteria and is where food is broken down by digestive juices and nutrients are absorbed into the bloodstream. This gut symbiosis allows for proper digestion and nutrient extraction.

In SIBO, food passes through the small intestine where the excessive bacteria disrupt the normal digestion and absorption process. Food is actually being fermented in the small intestine instead of the colon, and the bacteria are extracting all the nutrients from the food. This leads to bloating, gas, pain, and nutrient deficiencies.

New research is showing that SIBO is becoming more prevalent in celiac disease, IBS, leaky gut, and Crohn’s disease. Millions of Americans suffer from gastrointestinal distress each year and its evident that our digestive systems are under attack. It is important to be aware of SIBO and consider it a differential when diagnosing gastrointestinal symptoms.

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  • Millions of people worldwide suffer from poor gastrointestinal health.
  • SIBO is becoming more prevalent amongst individuals with GI disorders.
  • SIBO can affect children and adults of all ages.
  • SIBO is usually associated with an underlying condition.

Pathophysiology of SIBO

There are three main problems that arise with SIBO. The overgrowth of bacteria causes digestion to occur in the small intestine instead of the colon. This leads to malabsorption of vitamins and minerals, IBS symptoms, and damage to the GI tract lining. Fat-soluble vitamins, B vitamins, and iron deficiencies occur due to altered digestion and malabsorption.

Gas, bloating, cramping, and abdominal distension occur after eating. Tight junctions between endothelial cells in the gut lining become loose and weaken the intestinal barrier leading to leaky gut and an overactive immune response. The excess of bacteria in the small intestine negatively impacts the gut mucosa layer, immune system, and entire digestive process.

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Risk Factors for SIBO

There are many risk factors for SIBO. It can be caused by a multitude of things. Risk factors for SIBO include aging, the use of proton-pump inhibitors (PPIs), like omeprazole, improper small intestine functioning, diverticulosis, chronic pancreatitis, low stomach acid production, celiac disease, blind loop syndrome, injury, fistula, and diabetes.

As we get older, gastric motility decreases and digestion slows down. PPIs block the production of stomach acid which is used to break down food in the stomach before it goes to the small intestine for nutrient absorption. Long term use of PPIs can lead to vitamin and nutrient deficiencies, like B12, zinc, magnesium and calcium deficiencies, which causes chronic conditions, like osteoporosis and megaloblastic anemia.

Individuals with celiac disease still pose a risk for SIBO even if they adhere to a gluten free diet. There is an abundance of risk factors for SIBO that must be assessed before getting to the root cause of it.

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Signs and Symptoms of SIBO

Similar symptoms to IBS accompany SIBO. Gas, pain, bloating, nausea, vomiting, diarrhea, fatigue, and joint pain are common. Nutrient deficiencies are most likely present due to malabsorption. Vitamins A, D, E, K, iron, and B-12 deficiencies are most common.

Accompanying skin conditions, like rashes, acne, and roseaca may also be present. Anxiety and depression can also occur. SIBO affects the gastrointestinal tract, the skin, brain, and all enzymatic and metabolic processes.

Diagnosis and Testing

The gold standard test for SIBO is a hydrogen breath test. It measures the amount of gas produced by the bacteria in the small intestine. Preparation for the breath test starts two days beforehand with a special diet. The day of the test, the individual drinks a sugar containing solution to to feed the bacteria.

The breath test is then performed and measures the concentration of hydrogen and methane in the body. The only way the human body produces these gases is through the presence and output of bacteria. SIBO is diagnosed when a certain level of gas is found from the breath test.

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Treatment + Management

Treatment for SIBO is individualized and depends on the severity of bacterial overgrowth and gut dysbiosis. It can be difficult to treat and takes patience. Your primary healthcare provider along with a gastroenterologist or functional medicine practitioner should be seen for continuous, unresolved gastrointestinal symptoms.

SIBO is usually treated with an oral antibiotic, such as, rifaximin, and a SIBO diet. Rifaximin helps kill off bad bacteria, but also reduces the healthy bacteria necessary for proper digestive functioning.  In some cases, long term antibiotic treatment may be warranted. The SIBO diet has two phases. Phase 1 is the FODMAPS elimination diet and phase 2 is the GAPS diet.

A healthy diet, exercise plan, lifestyle changes, and adding in nutritional supplements are all part of getting the body back into balance, which is the overall goal of SIBO management.

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SIBO Supplements

SIBO causes many vitamin and mineral deficiencies, which over time can lead to malfunctioning of enzymes, metabolism disregulation, a weakened intestinal barrier, and different chronic diseases. It is of the upmost importance for individuals with SIBO to supplement.

Supplements are highly recommended. It is imperative to correct any nutrient deficiencies. A high-quality multivitamin, zinc and iron supplement, a B-complex, and probiotic should be taken daily. In more sever cases, digestive enzymes may be warranted too.

Keys to Success

  • Smaller, frequent meals, about 5-6 a day, rather than 3, are recommended for individuals with SIBO. This allows the body to digest food more efficiently.
  • Chew food thoroughly.
  • Optimal hydration, 6-7 bottles of water a day, is essential for proper digestion and gastric motility.
  • Stress management and a daily mindfulness practice is crucial for gut symbiosis and normal immune response.
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SIBO + Self-Awareness

Get to know yourself and your gut. Record in a journal what you ate for each meal, which foods were eliminated, and how you felt after each meal. Sit with yourself. A daily meditation practice promotes vagus nerve activation and a healthy rest and digest response. Be mindful, do not overeat. Eat smaller meals 5-6 times a day and chew food thoroughly. Drink lots of water. Nourish your gut, brain, mind and body.

Final Thoughts

SIBO is an overgrowth of bacteria in the small intestine that leads to gas, bloating, pain, and nutrient deficiencies. It is becoming more prevalent and gaining more recognition as a diagnosis for gastrointestinal symptoms amongst healthcare providers. Remember, you are not alone and you can be healthy. You are the CEO of your own health.

Thank you for reading this article.


This content is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of such advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.