SIBO Symptoms: What Doctors Miss & How to Test for It

You’re doing everything right – eating clean, taking probiotics, exercising – but you still feel bloated, tired, and frustrated. Your doctor says your tests are “normal,” yet you know something isn’t right. 

What if I told you that SIBO, a condition affecting approximately 35.5% of people with IBS when diagnosed by breath testing¹, might be the missing piece of your health puzzle? 

Small Intestinal Bacterial Overgrowth is one of the most overlooked gut conditions in conventional medicine, and it could be sabotaging your health in ways you never imagined.

After two decades of clinical practice and working with thousands of patients, I’ve seen too many people suffer needlessly because they – and their doctors – didn’t know about SIBO. 

The good news? Once you understand what you’re dealing with, you can take targeted action to reclaim your health.

In this article, you’ll discover what SIBO really is and why it’s so commonly missed by conventional medicine, learn to recognize the surprising symptoms that extend far beyond digestive issues, understand the two main types of SIBO and how they affect your body differently, and get a clear 3-step action plan for proper testing and treatment. 

Most importantly, you’ll understand why the interconnected approach to healing is essential for lasting SIBO recovery.

Ready to stop guessing and start getting real answers? Get your comprehensive gut testing package here and discover what’s really happening in your digestive system.

Key Takeaways

• SIBO affects 35.5% of IBS patients when diagnosed by breath testing but is rarely diagnosed because most doctors aren’t trained to recognize it or test for it properly¹.
• Two types exist: Hydrogen SIBO (causes diarrhea) and Methane SIBO (causes constipation) – knowing which type you have determines your treatment approach⁴.
• Symptoms extend far beyond digestion including brain fog, chronic fatigue, joint pain, skin problems, and mood issues due to the gut-brain connection⁶.
• Standard probiotics can make SIBO worse by feeding the bacterial overgrowth – this is why testing before treatment is crucial¹⁹.
• Proper diagnosis requires breath testing combined with comprehensive gut assessment including food sensitivity and gut permeability markers¹⁴.
• Root causes must be addressed such as previous infections, chronic stress, medications, or motility issues – otherwise SIBO typically returns¹⁷.
• The interconnected approach works best because SIBO affects multiple body systems and requires comprehensive healing protocols, not isolated treatments.

What exactly is SIBO?

SIBO, or Small Intestinal Bacterial Overgrowth, occurs when bacteria that normally live in your large intestine migrate upward and colonize your small intestine². 

Think of it as having a party in the wrong room of your house – the bacteria aren’t necessarily “bad,” they’re just in the wrong place causing chaos.

Your small intestine is designed to be relatively sterile compared to your colon. When bacteria set up shop there, they ferment the food you eat before you can properly absorb nutrients, creating gas, inflammation, and a cascade of symptoms that extend far beyond your digestive system³.

There are two main types of SIBO, classified by the gases these misplaced bacteria produce:

Hydrogen SIBO involves bacteria that produce hydrogen gas, typically causing diarrhea, cramping, and rapid gut transit. Patients often describe feeling like food “goes right through them.”

Methane SIBO (also called IMO – Intestinal Methanogen Overgrowth) involves methane-producing bacteria called archaea. This type typically causes constipation, as methane gas slows down gut motility⁴. 

Many patients with methane SIBO feel like their digestive system has “shut down.”

Some people have both types – what we call hydrogen-methane mixed SIBO – which can create alternating diarrhea and constipation, leaving patients feeling completely unpredictable.

The Symptoms That Go Beyond Your Gut

Here’s where SIBO gets tricky, and why so many doctors miss it. While digestive symptoms are common, SIBO often shows up as seemingly unrelated problems throughout your body. 

This is what I call the interconnected approach to health – everything in your body is connected, and when your gut is compromised, it affects every system.

Digestive symptoms include bloating (especially after meals), abdominal pain, diarrhea or constipation, excessive gas, and food sensitivities that seem to multiply over time⁵.

Systemic symptoms are where SIBO really reveals its whole-body impact. 

Brain fog is incredibly common because bacterial toxins can cross into your bloodstream and affect cognitive function⁶. 

Chronic fatigue occurs because SIBO interferes with nutrient absorption, particularly B vitamins essential for energy production⁷.

Many patients experience joint pain and muscle aches due to the inflammatory cascade triggered by bacterial overgrowth⁸. 

Skin problems like rosacea, eczema, or unexplained rashes often improve dramatically when SIBO is treated⁹.

Mood issues including anxiety and depression are surprisingly common with SIBO. Your gut produces about 90% of your body’s serotonin¹⁰, so when gut bacteria are out of balance, your mood pays the price. 

Weight fluctuations, both unexplained weight gain and difficulty gaining weight, are also red flags for SIBO¹¹.

Suspect you might have SIBO? The interconnected nature of these symptoms is exactly why I created the Interconnected series – the comprehensive guide to gut healing that addresses root causes, not just symptoms.

Why Your Doctor Might Be Missing SIBO

Unfortunately, many conventional doctors aren’t trained to recognize or test for SIBO. 

Medical school spends very little time on functional gastroenterology, and most doctors are taught to treat symptoms rather than investigate root causes¹².

The standard approach often involves prescribing acid blockers for digestive symptoms, which can actually make SIBO worse by reducing stomach acid that normally keeps bacteria from migrating upward¹³. 

Or patients are told they have IBS and given symptom management strategies without ever investigating what’s causing their IBS in the first place.

This is exactly why I always say “test, don’t guess.” 

As I discussed in my previous podcast on testing the gut instead of guessing, throwing supplements at symptoms without understanding the underlying problem is like trying to fix a leaky roof by putting buckets on the floor.

The SIBO Testing Protocol: Getting Real Answers

Proper SIBO testing involves a lactulose or glucose breath test that measures hydrogen and methane gases produced by bacteria in your small intestine¹⁴. 

The test is simple – you drink a sugar solution and breathe into tubes every 20 minutes for 2-3 hours. Elevated gas levels at specific time intervals indicate bacterial overgrowth.

However, SIBO testing is just one piece of the puzzle. In my clinical experience, the most effective approach combines SIBO breath testing with comprehensive gut assessment including:

Food sensitivity testing (like the FIT22 panel) to identify which foods are triggering inflammation. Many SIBO patients develop multiple food sensitivities as their gut lining becomes compromised¹⁵.

Gut permeability markers including zonulin and occludin help us understand if you have leaky gut, which often accompanies SIBO¹⁶. 

As I’ve seen in my work with Dr. Ken Brown and other experts featured in Beyond the Scope: Gut Health, Polyphenols, and the Real Medicine of Lifestyle, addressing gut barrier function is crucial for lasting SIBO treatment success.

Comprehensive stool analysis reveals the state of your large intestine microbiome, digestive function, and inflammatory markers that help guide treatment decisions.

The key is getting a complete picture before starting treatment. SIBO rarely exists in isolation – it’s usually part of a larger pattern of gut dysfunction that requires a comprehensive approach to heal effectively.

Your 3-Step Action Plan for Suspected SIBO

If you recognize yourself in these symptoms, here’s your practical next step protocol:

Step 1: Get Proper Testing 

Don’t waste another month trying random supplements or restrictive diets without knowing what you’re dealing with. 

SIBO breath testing combined with comprehensive gut analysis gives you the roadmap for effective treatment. 

Work with someone experienced in functional medicine who understands how to interpret these tests properly.

Step 2: Address Root Causes 

SIBO doesn’t happen in a vacuum.

Common underlying causes include previous food poisoning, chronic stress, medications (especially antibiotics and acid blockers), and structural issues affecting gut motility¹⁷. 

Your treatment plan needs to address why you developed SIBO, not just clear the current overgrowth.

Step 3: Implement a Comprehensive Healing Protocol 

Effective SIBO treatment typically involves multiple phases: clearing the overgrowth, healing the gut lining, restoring healthy motility, and preventing recurrence. 

This might include targeted antimicrobials, gut barrier support, prokinetic agents to restore proper gut movement, and carefully selected probiotics at the right time¹⁸.

The mistake I see most often is patients trying to treat SIBO with probiotics alone, or jumping straight to harsh antimicrobials without addressing underlying causes. This piecemeal approach rarely provides lasting relief and often makes symptoms worse.

The Interconnected Approach to SIBO Healing

What makes SIBO particularly challenging – and why so many people struggle with recurrence – is that it’s never just about bacteria in your small intestine. 

SIBO is a symptom of deeper imbalances in your digestive system, immune function, stress response, and overall health.

This is why I developed the interconnected approach to healing. 

Your gut health affects your brain function, your sleep quality impacts your digestion, your stress levels influence your gut bacteria, and your nutrition choices affect every system in your body. 

You can’t successfully treat SIBO by focusing on just one piece of this complex puzzle.

The most successful SIBO patients I work with understand that healing requires addressing multiple systems simultaneously. 

They optimize their sleep to support gut repair, manage stress to reduce inflammation, support their liver to handle bacterial toxins, and gradually rebuild their microbiome once the overgrowth is cleared.

Why Testing Beats Expensive Supplements Every Time

I can’t tell you how many patients come to me with cabinets full of expensive probiotics, digestive enzymes, and gut supplements that aren’t helping – or are actually making their symptoms worse. 

Here’s the thing: if you have SIBO, many standard gut supplements can feed the bacterial overgrowth and increase your symptoms¹⁹.

This is exactly the “thorn in your shoe” metaphor I use with patients. If you have a thorn in your shoe, you don’t need better socks or more comfortable shoes – you need to remove the thorn. 

Similarly, if you have SIBO, you don’t need more probiotics or digestive support – you need to clear the bacterial overgrowth first.

Don’t spend another month guessing what’s wrong.

Get tested with our FIT22 + Gut Permeability package and get a personalized consultation with one of our health coaches. 

You’ll save money, time, and frustration by getting real answers instead of throwing supplements at symptoms.

Moving Forward: Your Path to Gut Health Recovery

SIBO might feel overwhelming when you first learn about it, but I want you to know that it’s absolutely treatable when approached correctly. 

I’ve seen thousands of patients go from chronic digestive misery to vibrant health once they understand what they’re dealing with and implement the right protocol.

The key is patience and persistence. 

SIBO didn’t develop overnight, and it won’t resolve overnight. 

But with proper testing, comprehensive treatment, and an understanding of how all your body systems work together, you can absolutely reclaim your digestive health and overall vitality.

Remember, your symptoms are your body’s way of asking for help. Don’t ignore them, and don’t let anyone tell you they’re “all in your head” or that you just need to “manage” your IBS. 

You deserve real answers and effective treatment.

SIBO is just one piece of the gut health puzzle, but it’s often the piece that, once addressed, allows everything else to fall into place. 

Your journey to optimal health starts with understanding what’s really happening in your body – and that starts with proper testing.

Ready to take the next step? Learn the complete SIBO healing protocol in our Interconnected series and discover how addressing root causes – not just symptoms – can transform your health from the inside out.

Sources

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