SIBO symptoms may include abdominal bloating, constipation, and nutritional deficiencies.
SIBOcan affect adults and children at any age.
This article describes symptoms and causes of SIBO.

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The cause of symptoms can work both ways, too.
Common effects of SIBO include:
Additional symptoms may occur due to specific underlying causes of SIBO.
For example, a vitamin D deficiency can affectbone health.
What Color Is SIBO Poop?
SIBO and related conditions can cause your stool tochange colors.
Phone app tools can help you identify possible causes of stool shape and color.
This decreased intestinal motility means that bacteria in the small intestine stays for a longer time than usual.
This disrupts the normal balance ofdigestive enzymes.
What Is Blind Loop Syndrome?
Blind loop syndrome comes up whenever food digestion bypasses a part of your intestine.
Malnutrition
SIBO can interfere with your absorption of essential nutrients.
Bacteria naturally found in the small intestine aid in the breakdown and absorption of nutrients and help prevent infections.
Symptoms of malnutrition can include fatigue, weight loss, and depression.
Foods That Trigger SIBO
There’s research evidence to suggest that high-fiber diets improve SIBO symptoms.
For example, malabsorption of carbohydrates can cause bloating and gas when they ferment in the gut.
Speak with a healthcare provider before making dietary changes, especially if you have an existing digestive disorder.
Ask about medications and supplements, too, that can affect your digestion and nutrient absorption.
Risk Factors
A variety of illnesses may predispose you to SIBO.
Your healthcare provider may consider diagnostic testing if you have symptoms of SIBO without an obvious predisposing cause.
They are building on an understanding of how gut bacteria relates to the immune system or cognitive function.
Each method has benefits and limitations, but the direct sampling method is considered to be the most reliable.
The presence of hydrogen or methane is indicative of malabsorption.
Jejunal Aspiration
This is an invasive test in whichendoscopyis used to sample fluid from the small intestine.
Antibiotic Trial
Another diagnostic method involves beginning antibiotic treatment of SIBO and assessing the response.
If SIBO symptoms respond to antibiotics, there is no need to repeat diagnostic testing.
How to Treat SIBO
If you have SIBO, you will need treatment for the condition.
You might not need to use all of these methods, based on your specific condition.
For example, antibiotics may be useful in treating SIBO symptoms in people with IBD.
But there is limited research on how effective the antibiotics are in these cases.
Discuss recurring symptoms with your healthcare provider so that flare-ups can be treated promptly.
Antibiotics
A number of antibiotics can be used to reduce bacteria in the small intestine.
Up to 44% of people will experience recurrence within nine months after one course of antibiotics.
You may need antibiotics more than once.
Your treatment plan depends on several factors.
Some healthcare providers recommend stopping these treatments if you are diagnosed with SIBO.
Dietary Modifications
Dietary modifications may be helpful as adjunctive therapy for the treatment of SIBO.
Herbs have not been found effective for managing SIBO.
Tell your healthcare provider about any supplements that you use, because they may actuallypromotepH changes or bacterial overgrowth.
Symptoms are due to changes in gut bacteria growth, for which there are a variety of possible causes.
Treatment for SIBO can include diet interventions and medication.
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