Constant Bloating and Digestive Issues – SIBO could be the missing piece.

Small intestinal bacterial overgrowth (SIBO) occurs when bacteria become excessive in the small intestine causing a wide range of digestive and systemic symptoms.

It can be associated with irritable bowel syndrome (IBS) and is commonly one of the main causes of IBS symptoms, although it is not the sole cause for everyone.

Within the small intestine, food we consume can be used by the bacteria themselves to further fuel their growth. When this happens, they produce gas – methane, hydrogen, (and sometimes hydrogen sulphide) which then can contribute to symptoms. Over time, this could effect nutrient absorption in some individuals.

Common Symptoms of SIBO can include

(These symptoms can vary and are not specific to SIBO alone.)

What causes SIBO?

There are several possible contributing factors, including:

• Low stomach acid: Stomach acid helps limit bacterial migration into the small intestine. Reduced acid levels (for example with long-term PPI use or other causes) may increase risk.
• Impaired gut motility: The migrating motor complex (MMC) helps “sweep” bacteria and food through the small intestine between meals. If this process is disrupted, bacteria may accumulate.
• Previous gastroenteritis
• Immune system dysregulation
• Abdominal surgery (such as appendectomy or bariatric surgery), which can alter gut structure or movement.

Certain health conditions are also associated with a higher likelihood of SIBO, including diabetes, hypothyroidism, reflux disease, and some chronic gastrointestinal disorders.

What approach might a GP take?

If you see a GP, the focus is usually on assessing digestive symptoms and ruling out other medical conditions. If no concerning causes are identified, a diagnosis of IBS may sometimes be given.

Management may include:

• Symptom-directed medications (for bowel habit or pain)
• Limited dietary advice
• Further investigation such as endoscopy when clinically indicated

Where SIBO is strongly suspected or confirmed, antibiotic treatment may sometimes be considered.

How might a nutritional therapist approach SIBO?

A nutritional therapy approach typically aims to identify contributing factors and support long-term digestive health.

Possible steps may include:

• Functional testing: Such as breath testing measuring hydrogen and methane gases, alongside other assessments where appropriate (e.g. stool analysis or nutritional markers).
• Targeted dietary changes — often used temporarily to reduce symptoms and support treatment.
• Support for microbial balance — which may include nutritional or herbal strategies where appropriate and agreed upon with the client.
• Addressing underlying contributors, such as:
  • stomach acid and digestive function
  • gut motility and MMC support
  • nutrient deficiencies
  • stress and nervous system regulation
  • associated health conditions such as Thyroid support if necessary.

Every individual’s root causes and symptom patterns are different. A tailored plan that considers diet, lifestyle, digestive function, and overall health is key to long-term progress.

If this sounds familiar or resonates with your experience, feel free to get in touch by booking a free 15-minute discovery call to discuss your symptoms and possible next steps.

This information is for educational purposes only and is not a substitute for medical diagnosis or treatment. Always speak to your GP or healthcare provider regarding persistent or worsening symptoms.