Small Intestinal Bacterial Overgrowth (SIBO)

Introduction

Small Intestinal Bacterial Overgrowth (SIBO) is the presence of excessive bacteria in the small intestine. Gut motility disorders primarily cause SIBO. Peristalsis (gut motility) usually reduces the amount of food, microbes, and waste. However, when peristalsis gets disrupted, the microbes stay in the small intestine along with food and waste that feed the bacteria in the small intestine. SIBO can also be caused by ileocecal valve issues, which cause bacteria from the large intestine to enter the small intestine. Roux-en-Y and other illnesses, procedures, and medications can also be the cause.

There are three types of SIBO, which depend on the gases the bacteria produce. SIBO types include hydrogen, methane, and hydrogen sulfide. Usually, there is a "dominant" gas, but sometimes there can be a mix. Hydrogen-dominate SIBO usually causes diarrhea; whereas methane-dominant SIBO typically causes constipation. Hydrogen sulfide dominant SIBO (think sulfur), usually causes a rotten egg smelling flatulence, belching, or breath.

Symptoms

Bloating & gas
Diarrhea
Constipation
Uncomfortably full after eating
Acid reflux
Change in appetite
Bad breath
Chronic inflammation
Food sensitivities
Nutritional deficiencies (vitamins, minerals, macronutrients)
Unintended weight loss or gain
Leaky gut
Dysbiosis

Associated Diseases

Mood disorders
Irritable Bowel Syndrome (IBS)
Inflammatory Bowel Disease (IBD)
Crohn's Disease
Celiac's Disease
Metabolic diseases, including diabetes type I
Hypothyroidism
Fibromyalgia - at least 90% have SIBO

Interstitial cystitis (IC)
Chronic fatigue syndrome
Restless leg syndrome
Autoimmune diseases
Rosacea
Psoriasis
Parkinson's Disease
Ehlers-Danlos Syndrome (EDS)
Many more

Testing

SIBO testing is done using a breath test done at home. They're fairly simple but do require some prep and time.

Lactulose Trio-Smart is currently the gold standard in testing. It's the only test for all three types of SIBO. I usually recommend this testing for the first test. It helps to know what kind of SIBO you're dealing with. It requires a physician's prescription for testing and insurance coverage. Please ensure you get a lactulose breath test, not a glucose test!

Genova Diagnostics' 3-hour Lactulose Breath Test Kit is another great test. It tests for hydrogen and methane SIBO. It is also a great first test. It can be purchased directly through Direct Labs (link to Direct Labs). This test is also great if you don't have insurance.

FoodMarble AIRE Devices are fantastic tools. They're at-home devices that connect to your phone for an instant read of gas levels. The AIRE Device tests only for hydrogen and AIRE 2 tests for hydrogen and methane. Of course, the AIRE Device isn't as expensive as the AIRE 2, so it's good to know the type of SIBO you have before purchasing. These are especially useful after treatments and you notice SIBO symptoms returning. The downside is that lactulose is by prescription only, which means these tests can't accurately diagnose, The devices also don't give the exact measurements (ppm). Instead, it gives a "rating" from 1-10 of gas levels. I wanted to mention these devices as somewhat of a warning -- they're a great tool, but not for diagnosis.

Now what?