Understanding SIBO: A Functional Medicine Approach

By Carolyn McGillis, B.Sc., MN, NP.


Small Intestinal Bacterial Overgrowth (SIBO) is a condition where excessive bacteria populate the small intestine, leading to a variety of gastrointestinal symptoms. Unlike the large intestine, which naturally hosts a vast number of bacteria, the small intestine is supposed to have relatively low bacterial counts. SIBO disrupts this balance, affecting nutrient absorption and causing discomfort. Here, we’ll explore SIBO from a Functional Medicine standpoint, emphasizing the importance of identifying underlying causes and holistic treatment options.



What Triggers SIBO?

The root causes of SIBO are multifaceted and often interconnected. From a Functional Medicine perspective, it’s crucial to look beyond the symptoms to understand the individual’s unique health landscape. Key factors include:

  • Motility Issues: Certain conditions impede the digestive system’s ability to move food effectively, allowing bacteria to proliferate.
  • Anatomical Abnormalities: Gut structural issues can harbor bacteria, fostering their growth.
  • Medications: Extended use of certain drugs can disrupt normal stomach acid production, aiding bacterial survival.
  • Diet: High-sugar and carbohydrate diets can fuel bacterial overgrowth.
  • Impaired Immune Function: A weakened immune system struggles to maintain bacterial balance in the small intestine.


Recognizing SIBO Symptoms

SIBO manifests in various ways, commonly including bloating, gas, abdominal discomfort, bad breath, diarrhea or constipation, nausea, fatigue, and nutrient deficiencies due to malabsorption.


Diagnosing SIBO

A combination of symptom evaluation, medical history, and specific testing—predominantly breath tests measuring hydrogen and methane after sugar solution ingestion—helps diagnose SIBO.


Functional Medicine’s 5R Approach to Treatment

Functional Medicine addresses SIBO through the 5R Framework: Remove, Replace, Reinoculate, Repair, and Rebalance, aiming to restore bodily harmony.

  1. Remove: Eliminate dietary triggers, infections, and other gut stressors through elimination diets or targeted treatments.
  2. Replace: Supplement digestive secretions like enzymes and acids compromised by various factors, enhancing digestion and absorption.
  3. Reinoculate: Encourage beneficial bacterial growth with probiotic-rich foods/supplements and prebiotics, fostering a balanced gut microbiome.
  4. Repair: Nutrients such as zinc, omega-3s, and glutamine support gut lining repair, crucial for overall gut health.
  5. Rebalance: Lifestyle factors significantly impact gut health; managing stress, sleep, and exercise is vital for digestive wellness.


The Importance of Personalization

SIBO treatment necessitates a customized approach, reflecting each patient’s unique health landscape. A Functional Medicine practitioner can tailor strategies that address both symptoms and root causes, facilitating long-term health improvements.



Author: Carolyn McGillis, NP

I’m Carolyn, a passionate advocate for holistic health and well-being.

With licenses in Primary Health Care and Adult Nurse Practitioner, as well as certification in Functional Medicine, I bring a wealth of expertise to the field.

My own journey to wellness has inspired me to help others reclaim their health and vitality through personalized, compassionate care.






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