Small Intestinal Bacterial Overgrowth (SIBO) occurs as a result of excess bacteria in the small intestine. When the digestive system is functioning properly, food mixes with digestive juices in the small intestine breaking down food and nutrients begin to be absorbed into the bloodstream. The remainder of the digestive mixture continues to the large intestine, also known as the colon, where bacteria helps to further digestive food and essential nutrients are absorbed into the body. In a healthy digestive system, the majority of gut bacteria resides in the large intestine, and very little is in the small intestine. When bacteria enters and remains in the small intestine (i.e., SIBO), it can cause inflammation and damage to the intestinal lining, poor nutrient absorption and a host of not only gastrointestinal but also other bodily symptoms.
Types of SIBO
Hydrogen Dominant – when carbohydrates remain undigested in the small intestine they feed pathogenic or opportunistic bacteria. As these bacteria are fed, they create hydrogen gas. The gas then creates digestive challenges like bloating, cramping and diarrhea. Over time these bacteria multiple and exacerbate not only digestive symptoms, but can also result in fibromyalgia symptoms. Diarrhea associated SIBO can lead to weight loss as well.
Methane Dominant – now referred to as Intestinal Methanogen Overgrowth (IMO) – because archaea (a bacteria like organism) as opposed to actual bacteria, produce methane gas. IMO can occur in the small or large intestine and typically results in constipation, bloating, incomplete emptying and often weight gain..
Hydrogen Sulfide Dominant – when the sulfur metabolic pathway slows down or gets blocked, bacteria overgrow in attempt to get rid of excess sulfur. Symptoms include gastrointestinal, but also some experience hypersensitivity to pain, and become easily overstimulated to noise and sound.
With all three forms of SIBO, carbohydrates play a role in feeding the overgrowth which ultimate results in the production of a gas byproduct.
Contributing Variables to SIBO/IMO
- Dysregulation of the migrating motor complex (MMC) resulting in poor motility
- Obstructions, adhesions or other structure challenges
- Imbalance of bacteria
- Impaired digestion
- Low fiber and/or high sugar diet
- Use of pain medicines or NSAIDs
- Experiencing food poisoning or traveler’s diarrhea
- Chronic Stress
Often herbals (or antibiotics) and dietary changes are made to address the overgrowth. It is important to identify the root cause of the overgrowth. Without addressing the root cause, the restored balance will likely only be temporary.
Wondering if your IBS symptoms are SIBO related? Research shows there is a significant correlation between IBS-D and SIBO. For testing or to discuss if this is a variable for you, please get in touch.