What is SIBO? (Small Intestinal Bacterial Overgrowth)

Small Intestinal Bacterial Overgrowth (SIBO) occurs when bacteria accumulate excessively in the small intestine — and as a nutritionist in London, I often see how this imbalance disrupts digestion and contributes to persistent symptoms such as bloating, gas, and abdominal discomfort. Over time, SIBO can also impair nutrient absorption, increasing the risk of deficiencies and long-term digestive issues.

What Is SIBO?

The small intestine is meant to have relatively few bacteria. In SIBO, however, bacteria that usually live in the large intestine grow where they shouldn’t. This overgrowth can lead to fermentation of food, especially carbohydrates, resulting in gas, discomfort, and inflammation.

How Bacteria End Up in the Small Intestine

• Slow gut movement: When digestion is too slow, bacteria aren’t cleared from the small intestine.
• Past surgeries or gut issues: These can create pockets or changes in structure that trap bacteria.
• Use of medications: Long-term use of antibiotics or acid-reducing drugs can shift bacterial balance.
• Weak immune response: A low-functioning immune system may not regulate bacteria effectively.

SIBO Symptoms: What to Watch For

SIBO symptoms can mimic other digestive disorders, so they’re often overlooked or misdiagnosed. However, certain signs point clearly to bacterial overgrowth:

• Ongoing bloating or swelling in the belly
• Abdominal pain or cramping
• Excessive gas or belching
• Diarrhoea, constipation, or both
• Brain fog, tiredness, and poor concentration
• Unexplained iron or B12 deficiency

When Symptoms Persist

If your digestive symptoms don’t improve with general changes to diet or lifestyle, consider speaking with a qualified healthcare practitioner.
Getting to the root of the issue is key to long-term relief.

How SIBO Is Diagnosed

To confirm SIBO, healthcare professionals often use a simple breath test. The test involves drinking a sugar solution and then measuring the hydrogen or methane levels in your breath over time. Elevated levels suggest excess bacterial fermentation in the small intestine.

Why Breath Tests Work

The test works because bacteria produce specific gases when they ferment food. These gases enter the bloodstream and are released through your lungs.
Testing them helps detect where bacterial overgrowth may be happening.

Personalised Nutrition for SIBO

There’s no universal diet for SIBO. Each case is different and requires an individual plan tailored to symptoms, health history, and test results.

Why Diet Must Be Tailored

Some people respond well to structured short-term plans that reduce bacterial fermentation. Others may need a gentler, phased approach. The right plan depends on many factors, such as gas type, severity of symptoms, and underlying health conditions.

Phases of Support

• Symptom relief: Focus on easing digestive distress.
• Root cause support: Identify what led to SIBO and support healing.
• Maintenance: Build a long-term plan to reduce the risk of relapse.

Supplement Guidance: Use with Care

Supplements can play a role in SIBO support, but they’re not suitable for everyone. A professional can help you understand when and how to use them safely.

Common Types of Support

• Digestive aids that help with food breakdown
• Nutrient support if deficiencies are present
• Targeted herbal options where appropriate

Some probiotics may worsen symptoms in SIBO cases. Always seek guidance before starting anything new.

⚠️ Disclaimer: This article is for educational purposes only. Always consult a qualified medical professional before beginning any supplement or dietary protocol.

Lifestyle Habits That Support Gut Healing

• Eat at regular times: This supports gut motility and proper flow.
• Manage stress: Stress slows down digestion and weakens the gut-brain connection.
• Move your body: Light activity promotes intestinal movement and helps prevent stagnation.
• Prioritise sleep: Rest supports repair processes and hormone balance.

Building Sustainable Habits

Improving gut health takes time. With the right support, you can create realistic, long-term changes that encourage lasting recovery.

Why Personalised Support Matters

Every case of SIBO is different. Whether your symptoms are mild or more severe, a tailored strategy ensures that you’re supporting your body safely and effectively.

Conclusion

SIBO is a complex but manageable condition. With the right support, many people see real improvements.
By working with a trusted practitioner, you can take smart, practical steps toward better digestion and overall wellbeing.