Key Takeaways
- Small intestinal bacterial overgrowth (SIBO) is a digestive disease that occurs when bacteria from the large intestine enter the small intestine and grow, causing symptoms like bloating, gas, and diarrhea.
- Though constipation is not the most common SIBO symptom, it does occur, especially with methane-dominant SIBO.
- The best way to treat SIBO with constipation is to undergo medical treatment. Lifestyle changes like adjusting fiber intake, increasing exercise and hydration, and managing stress may also be beneficial.
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SIBO, or small intestinal bacterial overgrowth, is a gastrointestinal disorder that can cause many symptoms, including constipation.
Research on lifestyle interventions for SIBO is mixed, making it tough to know which strategy is best.
Read this article to learn more about SIBO-related constipation and how to manage it.
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The Link Between SIBO and Constipation
SIBO is a digestive condition that occurs when gut bacteria from the large intestine make their way into the small intestine and multiply. This can cause numerous symptoms, including:
- Bloating.
- Abdominal cramping.
- Gas.
- Diarrhea.
- Chronic fatigue.
While diarrhea is the more typical bowel pattern with SIBO, constipation can also be present.
Constipation tends to occur more often in SIBO cases where methane-producing microorganisms are the culprit of the overgrowth.
This is known as “methane SIBO” or “intestinal methanogen overgrowth” (IMO).
Increased methane production can slow intestinal transit time (or the rate at which food moves through the digestive tract). This can result in constipation.
Our free SIBO quiz can help you assess whether you may have SIBO.
8 Tips for Managing SIBO With Constipation
Treating the underlying cause of SIBO can improve digestive symptoms, including constipation.
The first-line treatment for SIBO is antibiotic therapy, though there are cases where symptoms continue after treatment.
Management of constipation may look different depending on which type of SIBO you have.
Talk to your doctor and dietitian before making any significant dietary and lifestyle changes on your own.
1. Increase Your Fiber Intake
While increasing your fiber intake is a well-researched strategy for improving constipation, it’s not so simple with SIBO.
Certain fiber-rich carbohydrates are fermented by your gut bacteria, which can cause the harmful bacteria to continue to grow and cause symptoms if you have SIBO.
Examples include garlic, beans, wheat, cow’s milk, and certain fruits and vegetables. These are known as FODMAPs, or “Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols.”
Many clinicians recommend a low-FODMAP diet as part of treating SIBO, but the evidence regarding the effectiveness of this approach is mixed.
Some studies have shown that vegetarian and vegan diets (typically high in fiber) and eating patterns rich in complex carbohydrates can help reduce harmful bacteria growth.
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2. Stay Hydrated
Making sure you drink enough water on a daily basis is an important part of managing SIBO with constipation.
Experts suggest females drink between six and nine cups of water daily and males drink between eight and twelve cups per day.
Your fluid needs may be higher if you live in a warm climate, exercise frequently, or have certain medical conditions.
If you’re not currently meeting your hydration goals, think about ways to increase your daily water intake, such as:
- Filling up reusable water bottles at the beginning of the day.
- Trying a hydration reminder app.
- Using flavoring options like herbal tea and fruit-infused water.
However, research shows that increased hydration only improves constipation in people who were previously under-hydrated.
3. Exercise Regularly
Along with many other benefits, regular physical activity may help improve constipation associated with SIBO.
Research shows that people with higher levels of exercise experience more frequent bowel movements and a lower risk of constipation.
A study from 2021 found that people who went on a 10-15 minute walk after each meal experienced improvements in gastrointestinal symptoms like bloating, gas, and abdominal pain.
Most people need at least 150 minutes of moderate-intensity aerobic activity each week.
This can be broken down however you wish, such as 30 minutes five days per week or into shorter, more frequent increments.
4. Practice Relaxation Techniques
Learning relaxation strategies like deep breathing and mindful eating can be useful for managing SIBO with constipation.
Increased levels of psychological stress have been linked with increased constipation symptoms.
This can become a challenging cycle because experiencing a digestive disorder like SIBO can impact your quality of life, cause pain, and increase stress.
A study from 2022 found that participants with irritable bowel syndrome (constipation type) who engaged in slow, deep breathing activities over six weeks experienced improvements in their digestive symptoms and a greater frequency of bowel movements.
Another study from 2019 explored how practicing mindful eating techniques may reduce stress around eating and improve digestion.
Common strategies for mindful eating include:
- Eating slowly.
- Practicing deep breathing prior to meals.
- Listening to internal hunger and fullness cues.
- Enjoying the taste, texture, and aroma of food.
- Limiting distractions during meals.
5. Avoid Trigger Foods
As with any digestive disease, you may notice specific foods that make your SIBO symptoms worse.
Trigger foods will be different from person to person. To help identify your possible triggers, consider keeping a food and symptom log.
Start writing down what you eat and drink, along with your symptoms and their severity.
If you notice any trends, bring this information to your dietitian, who can help you unpack what is going on.
You may find that refined sugars and high FODMAP foods worsen your symptoms, but overall, there is limited evidence of the benefit of specific SIBO diets.
6. Consider a Probiotic
Some research shows that probiotic supplementation can help decrease bacterial growth in the small intestine, improving symptoms in patients with SIBO. P
robiotics may also help antibiotic treatment work better in the management of SIBO.
However, there is mixed evidence on recommending probiotic supplements to treat SIBO. Some studies have found that taking probiotics may worsen SIBO symptoms.
In some cases, probiotic use has been linked with the development of SIBO, particularly methane-SIBO, which is linked with constipation.
All probiotic supplement brands contain different strains and concentrations of bacteria, making it possible for some to help SIBO and others to worsen the symptoms.
Talk to your doctor before starting any probiotics for managing SIBO symptoms.
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7. Limit Sugar Intake
Though the evidence is limited, some research shows that eating high-FODMAP foods may increase hydrogen output, which is one of the tests used to diagnose SIBO.
Consider limiting your intake of refined sugars high in FODMAPs, including:
- Honey.
- High fructose corn syrup.
- Sugar alcohols.
- Artificial sweeteners.
In general, a diet high in refined sugar is correlated with more constipation symptoms.
Research suggests this is due to sugary foods typically being low in fiber and high in fat.
8. Try Natural Laxatives
Certain foods have natural laxative qualities and are often recommended to manage constipation.
A popular example is prunes and prune juice. However, prunes are high in sugar and fiber, which may worsen SIBO.
If medical treatment of SIBO and lifestyle changes are not relieving your constipation, consider talking to your doctor about laxative options. There are many natural options, like magnesium citrate and senna.
Magnesium citrate is a saline laxative that draws water into the intestines, softening the stool.
Senna, available as a tea or over-the-counter supplement, works by increasing intestinal motility.
However, laxatives are not recommended for everyone with SIBO-related constipation.
Talk to your doctor before starting a natural laxative to ensure you choose a safe and effective option.
Takeaway
While constipation is not a common SIBO symptom, it does occur more frequently in methane-dominant SIBO.
The best way to manage constipation is to undergo treatment for SIBO and the underlying cause.
Diet and lifestyle factors may help with constipation as well, such as fiber, exercise, and stress management.
However, it’s best to talk to your doctor or dietitian before trying any home remedies.
How a Dietitian Can Help
It can be frustrating to see conflicting information online about managing SIBO.
If you’ve been diagnosed with SIBO and are unsure where to start regarding lifestyle changes, an experienced gut health dietitian can help you understand evidence-based recommendations.
Find a dietitian near you to get started today for as little as $0—94% of our patients pay nothing out of pocket.
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Frequently Asked Questions
Diarrhea is the most common bowel pattern in SIBO (small intestinal bacterial overgrowth). However, it’s possible to alternate between constipation and diarrhea. Constipation is also more common in a type of SIBO known as methane-SIBO or “intestinal methanogen overgrowth (IMO)”.
Treating the SIBO and the underlying cause will help improve digestive symptoms, including constipation. Work with your doctor and dietitian to identify lifestyle changes that may help SIBO with constipation, such as fiber, hydration, exercise, and stress management.
Constipation is most commonly a symptom of methane-SIBO, a type of small intestinal bacterial overgrowth. It’s characterized by an overgrowth of Archaea, resulting in the production of methane which causes digestive symptoms.
Because Archaea is not technically a bacteria, an alternative term, “intestinal methanogen overgrowth (IMO),” has been proposed for this condition.