Small Intestine Bacterial Overgrowth

Small Intestine Bacterial Overgrowth

SIBO, or Small Intestine Bacterial Overgrowth, is said to be one of the most under-diagnosed conditions. It’s risks, signs, and symptoms can mimic those of a few other conditions, making this one easy to overlook. But SIBO is actually very unique, and...

SIBO, or Small Intestine Bacterial Overgrowth, is said to be one of the most under-diagnosed conditions. It’s risks, signs, and symptoms can mimic those of a few other conditions, making this one easy to overlook. But SIBO is actually very unique, and if it’s severe it can prove difficult to treat. Because it can recur easily if not treated correctly, it’s been widely studied over the years due to its powerful and resilient nature.

 So What Exactly is SIBO?

 The infection in the small intestine occurs when bacteria from the large intestine (the colon) moves into the small intestine where they become trapped and begin to overgrow. In normal circumstances, the colon has 100,000 times more bacteria than the small intestine. This is designed specifically by the body for many reasons, but the main reason that the small intestine doesn’t host as many bacteria, good and bad, is so that vitamins and other nutrients can be absorbed by the blood stream before it reaches the harsh environment of the large intestine. In the case of SIBO, the small intestine can act like the colon. This causes an array of symptoms and issues. It’s also notable that there are two types of SIBO:

  • Methane Dominant- methane is produced by archaea (a type of microbe) and can lead to constipation in the SIBO positive patient.
  • Hydrogen Dominant- hydrogen is by byproduct of bacteria reproduction and can lead to diarrhea in the SIBO positive patient.

Leading Causes of SIBO

 Studies on SIBO are actually interesting, as there have been multiple studies spanning the years. However, with many different research results, the nature of the studies can change vastly between causes and effects, and even treatment methods. So far, what we do know about the causes are very reliable. The main causes being:

Stress- I don’t believe this one needs long scientific research, but studies have shown that it’s not just the brain that communicates with the stomach, but the gut bacteria that also communicates to the brain. Stress has been notorious for causing many health issues, so it’s no wonder that SIBO has a direct link to this when it comes to signaling reactions in both the brain and stomach when the body is under emotional or physical stress. Stress is also a main reason for SIBO’s return after it’s been treated.

Medications- In more serious situations, very brief and temporary use of medications are necessary in treating some symptoms of conditions and disease. However, the over-prescribing and excessive use of pharmaceuticals like antibiotics, pain medications, antacids, and NSAIDs can drastically alter the bacterial quality in the gut. We do need both good and bad bacteria in our digestive systems for the entire body to work correctly. Medications can cause a major disturbance in this symbiotic relationship, allowing for SIBO to occur.

Celiac Disease- This condition is often left undiagnosed, as often times it doesn’t even have symptoms until it’s caused serious damage. Patients with celiac who don’t know, or those who have it and don’t discontinue consumption of wheat and gluten cause damage to the lining of the intestinal tract. This damage is called “leaky gut”, and it can allow for bacteria from the colon to seep into the small intestine, attributing to SIBO.

Junk Foods- Poor food choices like fast foods, processed sugars and sweets, and soda can lower your stomach acid levels, and they can do it pretty quickly. Lowered or diminished stomach acids leads to undigested food, which leads to overgrowth of bacteria. This also can cause acid reflux type symptoms, making you think you have too much acid, and lead to taking antacids. This is a vicious cycle and, as per mentioned above, antacids themselves can lead to SIBO as well. Carbohydrates also seem to be the food of choice for bacteria, so people with high carb diets might find that if they have SIBO they’ll crave carbs and sugar more than usual. They may also notice that after consuming carbs, their symptoms may worsen.

Motility Disorders- Normal GI movement and motility is needed in order to sweep the debris effectively through the tract, using a migrating motor complex (MMC). If the MMC is impaired, this can cause motility issues and bacteria overgrowth. In the small intestine, this type of impairment can be caused by cirrhosis due to excessive alcohol use, gastric portal hypertension, chronic kidney issues, neuropathy, and aging.

Symptoms and Tests:

 There are many symptoms of SIBO that are common to other conditions, however these can be more pronounced and there are some very distinct to SIBO. Most people diagnosed with small intestine bacterial overgrowth state that it’s very painful, and can really interfere with daily life.

Severe Diarrhea- Some patients with SIBO report having to go the the bathroom within minutes after eating a meal high in carbohydrates. They also report severe pain along with their bowel movements. This is likely due to the hydrogen dominant SIBO, and associated overactive motility.

Constipation- Some patients with SIBO present with chronic constipation, and report a sensation that feels like their digestive system “just isn’t moving”. This is likely due to the methane dominant SIBO, and underactive motility.

*If you have either chronic diarrhea or constipation, see a healthcare professional right away

Bloating- But more than just an overeating bloat. SIBO sufferers report almost constant bloating with even more bloating and discomfort after carbs or sugar. This is no surprise, as most bacteria love these two foods, and probably become overactive once it hits the small intestine.

Abdominal Pain- Not just any old gas discomfort. Patients can suffer from upper left, right, or middle quadrant pain. This pain can feel like anything from a cramp to a burn and can even radiate (or refer) pain to the back and shoulders in more severe cases.

Gas- The type that really interferes with daily life like work, social interests, even your sex life.

Joint Pain- In some cases, patients who have undiagnosed SIBO over years will even complain of severe joint pain, particularly but not limited to the knees and ankles.

Extreme Weight Loss- Some patients with SIBO lose a significant amount of weight in a short amount of time. While this may sound like some people’s idea of a great way to trim fat, these patients are losing weight mostly due to malabsorption of vital nutrients and minerals, and chronic diarrhea.

If you are experiencing any of these symptoms, please see your healthcare provider right away! If SIBO is suspected, your doctor will likely order a Lactulose Test. This is a test that will be performed either in office or at home, where you’ll breathe into a device every 20 minutes for 3 hours. This will measure the levels of methane and hydrogen and give an accurate picture of what’s going on in your small intestine.


 Over the years, SIBO has proven to be a difficult condition to treat. More commonly in other treatment protocols, patients are given supplements and nutrients to add to their bodies. For SIBO, we must first wipe the entire digestive tract of good and bad bacteria. This is typically done with prescriptions of antibiotics, with the hopes that the good bacteria will repopulate on its own. After the use of antibiotics, we can begin to carefully reintroduce pre and probiotics to restore the microbiome. Diet also plays a very important role in treatment. During a SIBO protocol, it’s best to make digestion as easy as possible. The Elemental Diet is often times recommended to the patient, which is a diet consisting only of liquids containing fat soluble vitamins, amino acids, and electrolytes. An exception to having anything else on the elemental diet can be water, plain black coffee, and tea. Working with your doctor if you suspect SIBO or have been diagnosed will be key to treating it correctly. We recommend working with a professional that understands the importance of replenishing your body at the correct time during treatment. A lot of practitioners use the 4 R’s method, which is removing all of the bad things like irritating foods, replace enzymes and acids to help your stomach with digestion, reinoculate by putting good bacteria back into the gut, and finally repair using essential vitamins and minerals that will help seal up any damage caused by the bacterial overgrowth. A healthy digestive system is truly essential to good health! Make sure you’re getting the very best care by reaching out to our expert medical team at Gentera Center for Regenerative Medicine. Let us treat you properly, and restore your health!