Bloated, Gassy & Miserable? SIBO May Be the Sneaky Reason Why

Sep 01, 2026 0 comments

Judging by the ocean of digestive medications that you see in every drug store in America (as well as many grocery and department stores), I think it’s safe to say that there are a whole lot of us for whom “GBCD”—gas, bloating, constipation and/or diarrhea—is a regular occurrence.

Fair statement?

What makes this especially difficult is that there are a multitude of possible reasons why you’re bloated, gassy and have anything-but-normal BMs…so getting to the bottom of it can be tricky.

Conditions that can cause digestive woes include gluten sensitivity, irritable bowel syndrome (IBS), celiac disease, medication side effects, inflammatory bowel disease (Crohn’s and ulcerative colitis), food allergies and lactose intolerance.

But there is another possible cause that may not immediately come to mind.

It’s small intestinal bacterial overgrowth (SIBO).

Here’s the scoop on this sometimes-overlooked condition, what may cause it and what you can do if you suspect it may be affecting you.

Meet SIBO

To understand SIBO, you need to know a little bit about your innards.

Your GI tract contains an enormous and complex community of microorganisms, but they aren’t distributed equally throughout it. There are relatively few bacteria in your stomach and upper small intestine compared to the vast microbial population in your large intestine (colon).

This arrangement allows your stomach to carry out the preparatory breakdown of your foods, while your small intestine continues breaking them down and absorbing nutrients.

Then in the final stages of digestion, your bacteria-rich colon steps in to absorb water and electrolytes, break down certain carbohydrates and fiber, and (ideally) help create a healthy BM.

SIBO occurs when there is an excessive number or abnormal mix of bacteria in the small intestine.

When too many bacteria set up shop there, they can begin fermenting carbohydrates before they should. This fermentation produces gases, which can result in some very familiar complaints—bloating, abdominal discomfort, diarrhea and, in some people, constipation.

And because your small intestine is where much of your nutrient absorption takes place, significant or long-standing SIBO can interfere with that important job as well.

But wait! There’s more!

Unfortunately, the problems associated with SIBO aren’t necessarily limited to having to unbutton your pants after eating because you’re so bloated.

When digestion and nutrient absorption are impaired over time, nutritional consequences can develop. Depending on the severity and underlying cause, SIBO may be associated with:

Nutrient deficiencies
Malabsorption
Vitamin deficiencies, including vitamin B12
Unintentional weight loss
Fatigue
Changes in bowel habits

SIBO has also been associated with a variety of other digestive and systemic conditions, although researchers are still working to understand when SIBO is a cause, a consequence or something that simply occurs alongside them.

That’s one more reason why persistent digestive symptoms deserve some investigation instead of simply being covered up with an endless supply of antacids, laxatives or anti-diarrheal medications.

What causes SIBO and how is it diagnosed?

SIBO doesn’t usually pop up out of nowhere. Certain conditions can create an environment that makes it easier for too many bacteria to accumulate in the small intestine.

One particularly important factor is impaired intestinal motility—the normal muscular movement that keeps food, waste and bacteria traveling through your digestive tract.

SIBO has been associated with factors such as aging, digestive motility disorders, structural abnormalities of the digestive tract, previous abdominal surgery, diverticular disease and diabetes.

It also tends to occur more often in people with certain conditions that can affect digestion and motility, including an underactive thyroid (hypothyroidism).

SIBO is commonly evaluated with a breath test. This involves drinking a solution containing a carbohydrate such as glucose or lactulose and then breathing into collection tubes or bags at regular intervals.

The samples are analyzed for gases—typically hydrogen and methane—produced by microbes as they ferment the test solution.

But these tests are not foolproof and can sometimes produce inconsistent or difficult-to-interpret results. Your symptoms, medical history and possible underlying factors are important pieces of the puzzle too.

How to fight back!

Antibiotics such as rifaximin are commonly used to treat SIBO and could be helpful in some instances.

But there’s another extremely important piece of the puzzle:

Why did the bacterial overgrowth develop in the first place?

If an underlying problem with motility, digestion or another health condition isn’t addressed, simply reducing the bacterial population would likely not be the end of the story. SIBO can recur, which makes identifying and addressing contributing factors especially important.

Here are some additional measures that can help support your digestive system and encourage a healthier intestinal environment.

Eat the right carbs—for YOU

When your small intestine contains too many bacteria, certain carbohydrates can provide plenty of material for those bacteria to ferment.

And you know what fermentation creates?

Gas.

That’s why dietary changes can be an important part of getting uncomfortable symptoms under control.

Early on, some people find that temporarily reducing highly fermentable carbohydrates and certain high-fiber foods helps decrease gas and bloating while the underlying problem is being addressed.

But here’s where it gets tricky: There is no single perfect SIBO diet for everyone.

Foods that create major bloating for one person may be perfectly well tolerated by another. Your individual tolerance matters.

Depending on your symptoms, temporarily reducing foods that are particularly fermentable or difficult for you to digest may give your digestive system some breathing room. Lower-fiber choices such as cooked white rice, potatoes without the skin and well-cooked vegetables may be easier for some people to tolerate during this period.

But the goal isn’t to fear fiber forever.

As your digestive system improves, gradually working a greater variety of whole foods and fiber back into your diet as tolerated can help you maintain a nutritionally diverse diet and support your microbiome over the long term.

If you find yourself eliminating a long list of foods, working with a knowledgeable nutritionist can also help you maintain good nutrition while identifying the foods that work best for you.

And this should probably go without saying, but minimizing ultraprocessed foods and excessive refined carbohydrates is always a good idea for your gut and overall health.

Address the underlying factors

SIBO needs the right environment to take hold, so identifying the factors that may have put out the welcome mat is crucial.

For example, an underactive thyroid (hypothyroidism) can slow digestive motility and make it easier for bacteria to accumulate where they don’t belong.

Blood sugar problems and diabetes can also affect the nerves and muscles involved in digestion, while certain medications, previous surgeries and structural problems within the digestive tract can interfere with normal motility.

Looking at the whole picture—your digestion, diet, nutritional status, medications and overall health—can provide important clues about why your digestive system isn’t functioning as it should.

Support your army of beneficial bacteria

Your gut microbiome is an incredibly complex ecosystem, and supporting the beneficial bacteria that live there is an important part of overall digestive and immune health.

Certain probiotic strains have been studied for their ability to support bowel regularity, abdominal comfort and a healthy intestinal microbial balance.

Our own Super Shield multi-strain probiotic formula contains Lactobacillus paracasei, Lactobacillus plantarum and Bifidobacterium breve—species that have been studied for their effects on intestinal microbial balance and digestive symptoms.

Plus, Super Shield’s 12 additional probiotic strains each contribute to supporting a healthy intestinal environment and normal immune function.

Reduce stress

Stress and your digestive tract are closely connected through what researchers call the gut-brain axis.

Chronic stress can affect intestinal motility, digestive function and even the composition of your gut microbiome—which is not exactly what you want when you’re already dealing with digestive problems!

Do whatever you can to reduce stress in your life. Measures such as exercise, deep breathing, prayer, counseling, meditation, acupuncture, spending time outdoors and adopting a pet (if you love animals) can all be wonderful ways to help your mind and body decompress.

Your gut may thank you too.

To your health,

Sherry Brescia