What is SIBO? 

Small intestine bacterial overgrowth, better known as SIBO, is a challenge that many Americans face every year.SIBO

Although the small intestine is the longest section of the digestive tract, bacteria don’t typically like to make it their home. This is partially due to the presence of bile from the stomach that must be neutralized. Even more, food has a relatively quick flow through this portion of the digestive system. Bacteria prefer to live in the large intestine where the digested food hangs out longer. 

Small Intestine Bacterial Overgrowth Explained

In the case of SIBO, something is causing food to remain in the small intestine longer. Ultimately, this allows bacteria to thrive in an area that wasn’t designed to handle this kind of growth. The byproducts produced by the bacteria that take up residence in the small intestine irritate the mucous lining and interfere with nutrient absorption.  

Think of SIBO comparatively to invasive plants growing where you don’t want them. It may be the most beautiful plant, but if it’s somewhere it’s not supposed to be, it competes for food and light with the plants that are intended to be there. Similarly, bacteria that may be fine in the colon are detrimental to the gut in the small intestine. 

Risk Factors for SIBO 

Risk factors for small intestine bacterial overgrowth are anything that slows down the motility of food through the GI tract causing it to remain stagnant in the small intestine. These include hypothyroidism, abdominal surgery, structural defects in the small intestine, low stomach acid production, diverticulosis (small pouch-like pockets in the wall of the intestine), or any medication or disease that may slow down motility.   


Symptoms may look different for everyone. Common ones include bloating, cramps, constipation or diarrhea, heartburn, nausea, headaches, fatigue, eczema, abdominal pain, and vitamin B12 deficiencies. SIBO


The unwelcome bacteria living in the small intestine can compete with the bile there. This makes fat absorption difficult leading to fatty stools and poor absorption of the fat-soluble vitamins A, D, E, and K. Furthermore, the bacteria that produce vitamin B12 in the colon can become impaired from SIBO. 


There are two major methods of testing. One is invasive and gathers bacteria from the small intestine to culture and count. Unfortunately, it is difficult to gather these bacteria without damaging or contaminating them on the way back up. Thankfully, there is a second, less invasive option called the Lactulose Breath Test.

Lactulose is a man-made sugar that people are not able to digest, but bacteria can. While digesting the lactulose, the bacteria produce methane and hydrogen that pass through the intestinal wall into the bloodstream. Eventually, these byproducts are breathed out of the lungs and collected during the test.  

SIBO Resolution 

The goal of SIBO treatment is to reduce the number of bacteria in the small intestine. Traditionally, this is a multi-faceted approach. The primary method is to remove the foods that the bacteria living in the small intestine prefer to eat, which are sugar and lactose. A SIBO reduction diet includes foods low in fiber and other macromolecules. Furthermore, nutritional support is key for anyone suffering from SIBO, especially if they have lost weight or are deficient in critical vitamins and minerals.

Often, antibiotics are a traditional part of the care of SIBO. Unfortunately, antibiotics are non-discriminatory as to which type of bacteria they kill – good or bad. Always talk with your healthcare provider to decide what is best for your situation.  

Probiotics Can Help!

When researching remedies for SIBO, you may find mixed reviews on whether or not probiotics can help. However, strong scientific research and clinical experience both support the fact that probiotics can indeed aid in the recovery of small intestine bacterial overgrowth.

Firstly, a 2017 meta-analysis found that probiotics led to a roughly 53% eradication rate of small intestine bacterial overgrowth. Secondly, a 2022 clinical trial using Lactobacillus-containing probiotics led to a 25% SIBO eradication rate. So how do probiotics produce these results? Probiotics are actively antimicrobial! They’ve been shown to correct dysbiosis and SIBO, to promote motility, and to improve leaky gut.Flourish probiotic

Flourish probiotics have been used by practitioners who treat SIBO and have seen promising results.


The best thing to do to prevent SIBO is to keep things moving along in the gut. Keep things moving with fiber, fluids, and movement! SIBO prevention


 The content in this article is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health providers with any questions you may have regarding a medical condition.

Written by Lorilyn VanDyke and Kelsy Armstrong


Dukowicz, A. C., Lacy, B. E., & Levine, G. M. (2007). Small intestinal bacterial overgrowth: a comprehensive review. Gastroenterology & hepatology, 3(2), 112–122.

Mayo Clinic Staff. (2020, February 28). Small intestinal bacterial overgrowth (SIBO). Mayo Clinic. 

SIBO Center For Digestive Health. (n.d.). SIBO Test Overview. SIBO Center for Digestive Health.