SIBO Diet: What it is, how to get started, and how it can help you heal

This article has been medically reviewed by Michael Bass, MD, and Mayra Garcia-Zeda, MHSN, RD, LDN. It was written by Angela Myers.

Experiencing gastrointestinal discomfort is never fun. If that discomfort includes constipation, bloating, stomach pain, loss of appetite, or diarrhea, small intestinal bacterial overgrowth (SIBO) might be to blame. SIBO occurs when there’s an overgrowth of bacteria in the small intestine. While common, it’s also highly treatable. Treatment typically includes antibiotics and following a SIBO diet. But what exactly is a SIBO diet in the first place?

While we wish there was a simple answer to that question, the truth is, the right nutritional approach to manage SIBO symptoms differs from person to person. Fortunately, there is a process to discover what foods to eat and avoid in order to manage your SIBO symptoms. Ahead, we discuss the process to find SIBO triggers and actionable strategies to manage bacterial overgrowth in the small intestine. 

What is small intestinal bacterial overgrowth (SIBO)?

SIBO is exactly what it sounds like: an overabundance of bacteria in the small intestine. Our guts thrive on healthy bacteria in the right quantities and places. When our guts are operating business as usual, the large intestine has more (and more diverse) bacteria than the small intestine. 

When more bacteria—good or bad—end up in the small intestine than there should be, SIBO occurs. “There’s often a misconception that SIBO is an overgrowth of ‘bad bacteria’ in the gut,” explains Kaitlin Voicechovski, MS, RDN, LDN, Lead Registered Dietitian at Oshi Health, “It’s more accurate to think of it as bacteria simply hanging out in the wrong neighborhood.”

Getting gut bacteria out of the wrong neighborhood usually requires a multi-pronged approach: antibiotics prescribed by a gastroenterologist or another GI provider alongside lifestyle changes. Making nutritional changes is also important for treating and preventing future bacteria overabundance in the small intestine—but more on that later. 

SIBO signs & symptoms 

When too much bacteria moves into the small intestine, it can have far-reaching impacts on our health. Common SIBO symptoms include:

• Diarrhea 
• Bloating
• Abdominal pain and/or swelling
• Gas
• Constipation
• Feeling too full after eating
• Loss of appetite
• Unintentional weight loss 
• Mood changes

If you read that list of symptoms and thought they sounded similar to other gastrointestinal conditions, you would be correct. Diagnosing SIBO is tricky, since symptoms overlap with those stemming from other GI conditions. 

To make matters even more confusing, having other GI conditions, including IBS and Crohn’s Disease, is a risk factor for SIBO. Some research suggests over one third of people with other GI conditions experience SIBO too. Other risk factors for SIBO include being older, a history of abdominal surgery or cancer, and a weakened immune system. 

If experiencing the above symptoms (whether you have any, all, or none of the aforementioned risk factors), you should consult a team of GI specialists. SIBO is not something you can self diagnose, and DIYing treatment probably won’t end well either. Before your appointment, this GI diagnostic quiz from the Bloated Belly Whisperer may provide useful talking points. 

For Oshi patient M.K., working with GI specialists who understood SIBO and the best treatment options made all the difference. “My provider was very knowledgeable about SIBO,” says N.M., “I look forward to the next steps and have a plan of action.”

SIBO diet fundamentals

While nutrition alone can’t cure SIBO or address its root cause, it plays an important role in managing symptoms. “There are no diets that have been proven to treat SIBO,” Voicechovski explains, “But there is also no evidence that diet causes SIBO. Eating high FODMAP foods, carbohydrates, or any other food does not increase the likelihood of developing bacterial overgrowth.”

The good news? What you eat may play a role in symptom management, if someone already has SIBO. For those diagnosed with this GI condition, eliminating food triggers may help you avoid future SIBO flare-ups. To find these triggers, many turn to the low FODMAP diet.

Low FODMAP diet for SIBO

“FODMAPs are carbohydrates that are fermentable by our gut bacteria,” explains Voicechovski. The term is actually an acronym for fermentable oligosaccharides, disaccharides, monosaccharides and polyols (aka four carbohydrate groups that often  trigger GI symptoms). 

For SIBO specifically, reducing the amount of FODMAPs may eliminate any SIBO symptoms caused by the fermentation of FODMAPs in the gut, says Voicechovski.

However, you can’t just cut out FODMAPs without guidance. For one, identifying high and low FODMAP foods without guidance from a registered dietitian (RD) is a tall order. Second, the FODMAP diet is an elimination diet with specific steps to follow.

Those steps include:

• Elimination: during this first stage, all FODMAPs are eliminated from your diet. This phase lasts two to six weeks.
• Reintroduction: each lettered subgroup (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) is reintroduced one at a time so the individual can learn which ones cause symptoms. Reintroduction typically takes place over a six to eight week period.
• Personalization: once identified, a RD can help you tailor your meals so you avoid any triggers.

While the low FODMAP diet can be effective, it’s crucial to note that if SIBO isn’t medically treated, progressing beyond the elimination phase may be difficult.

We’ve said it before, and we’ll say it again: Only complete the low FODMAP diet under the guidance of a RD.

Foods to avoid

When undertaking the low FODMAP diet, it’s best to avoid high FODMAP foods, such as:

• Broccoli 
• Apples
• Pasta
• Watermelon
• Avocados
• Chickpeas
• Soy beans
• Salami 
• Sausage
• Any products with with barley, wheat, or rye
• Most, if not all, dairy products

Note: This list is not comprehensive. For a more complete list, click here.

Foods to eat

As you eliminate high FODMAP foods, you can swap them for gut-friendly options. Popular low FODMAP options include:

• Strawberries
• Tomatoes 
• Blueberries
• Oranges
• Eggplant
• Unprocessed meats
• Seafood
• Oatmeal
• Rice
• Nuts, any kind besides cashews and pistachios
• Almond milk
• Butter

Note: This isn’t every low FODMAP option out there. For a more comprehensive list (and recipes), check out our free cookbook. 

Other dietary approaches

Other dietary approaches, such as the elemental diet, are sometimes recommended to manage SIBO symptoms. The elemental diet consists of liquid meals with the basic “predigestive nutrients” our body needs to function (i.e. amino acids, vitamins, short-chain triglycerides, minerals, electrolytes, and short-chain maltodextrins). 

When well-tolerated, this diet can help manage symptoms of multiple GI conditions, including SIBO. However, the diet’s rate of intolerance is over 40%, not to mention a liquid only diet isn’t always accessible or socially acceptable. 

Voicechovski notes that strict dietary approaches like this one aren’t ideal for managing SIBO symptoms. She instead recommends finding and eliminating any food triggers (aka trying out the FODMAP diet) and swapping them for foods that can help manage symptoms.

Managing gut bacteria

Since SIBO involves an overgrowth of bacteria in the small intestine, treatment focuses on reducing the excess bacteria rather than simply rebalancing the gut microbiome. To do so, there are a few must-haves to add to your plate (or supplement line-up):

• Vitamin B-12: “Individuals with SIBO are at a higher risk for B12 deficiency, so focusing on foods rich in B12 such as fish, beef and nutritional yeast or supplementing as needed until levels return to normal should be considered,” says Voicechoski. 
• Fiber: fiber is your gut’s best friend. It supports healthy gut bacteria and can reduce symptoms of many GI conditions. A soluble fiber supplement may be recommended to reduce SIBO symptoms. 

When it comes to supplements, however, you and your RD should be discerning. “There are many supplements on the market touted as a solution for SIBO, and while they may sound enticing, evidence to support them falls short,” says Voicechovski. 

One supplement she points out? Probiotics. While probiotics can prevent or treat other Gi conditions, including IBS and IBD, they are unlikely to help treat SIBO. They may even put you at risk of a SIBO recurrence, Voicechovski adds. 

Lifestyle and SIBO management

“It’s important to note that the low FODMAP diet cannot treat SIBO, rather it can be used as a symptom management tool before and/or alongside treatment,” says Voicechovski. Other SIBO management strategies include improving  meal hygiene, starting a food diary, and staying hydrated.

Improve meal hygiene

When Voicechovski works with individuals diagnosed with SIBO, she not only focuses on what they eat, but how they eat. Good meal hygiene can improve digestion and reduce GI symptoms. More specifically, she recommends staying present while eating. 

Mindful eating hygiene can include:

• Listening to hunger and fullness cues 
• Sitting down to eat
• Not watching TV while eating
• Focusing on the smell and taste of what you’re eating
• Chewing food slowly
• Setting down utensils between bites
• Eating from a well-portion plate

“While these changes sound simple, they can often be really effective for better digestion and management of unwanted symptoms,” says Voicechovski.  

Keep a food diary

When one of Oshi’s patients undertakes the low FODMAP diet, our RDs often recommend starting a food diary. A food diary is a great way to track when SIBO symptoms occur and which foods you ate around that time. 

This food and symptom log can help identify patterns. If, for example, you experience SIBO symptoms after Friday nights drinking with friends, alcohol may be one of your triggers. By documenting symptoms, food eaten, and drinks consumed each Saturday morning, it will be easier to identify that alcohol is a trigger for you.

You can write in your food diary at each meal or once a day, depending on your preference. Logging daily (or multiple times a day) is a great way to increase awareness of your symptoms and what you eat. 

Stay hydrated

Hydration is key, especially if you have SIBO. A 2022 study looked at how water origin and daily intake impacted gut health in the US and the UK. The researchers’ conclusion: drinking ample water and opting for tap, filtered, or bottled water over well water supports strong gut health. It’s also important to avoid drinking contaminated water (which can include tap water in certain regions in the U.S. and abroad). 

Drinking “enough” water can be difficult to define. While there’s a common myth that you should drink 64 ounces a day, one size doesn’t fit all. Instead, the amount of water you need depends on your gender, activity levels, and age.

Sugary drinks and caffeine may also be triggers for SIBO symptoms. If this is the case for you, consider swapping your afternoon coffee or coke out for something more hydrating, like water or tea. 

SIBO recovery and relief

As we’ve discussed, nutritional changes alone won’t treat SIBO. Your GI provider may also recommend antibiotics, the first line of defense against SIBO.

Commonly prescribed antibiotics for SIBO include:

• Amoxicillin-clavulanate
• Ciprofloxacin
• Doxycycline
• Metronidazole
• Neomycin
• Norfloxacin
• Tetracycline
• Trimethoprim-sulfamethoxazole 
• Rifaximin

These antibiotics are a quick-fix, not something you’ll utilize for months or years. To complement these short-term solutions, a provider may also recommend the nutritional and lifestyle changes mentioned above.

However, there isn’t one SIBO treatment plan; instead SIBO recovery should be customized to your needs and take into account the many aspects of your life and what you eat.

For M.D., a customized approach that was easy to follow provided SIBO relief. They reflected,  “My Oshi provider was great—thoughtful and a good listener. She proposed a sensible plan for treating my SIBO.”

Frequently asked questions

What does a SIBO diet consist of?

A SIBO diet is highly personalized. Usually, it involves identifying and avoiding food triggers. This can be done through an elimination diet, such as the low FODMAP diet. A RD may also recommend supplements containing B-12 or fiber. 

What foods should you avoid with SIBO?

Foods that trigger SIBO are personal. Fried foods, for example, may make SIBO symptoms worse for one person, but not another. Consulting with a RD can help you determine your personal triggers and guide you through following the low FODMAP diet effectively

Can you “starve out” bacteria overgrowth?

It is not scientifically proven that you can “starve” bacteria to eliminate SIBO, but reducing FODMAP intake can help manage symptoms. These food triggers vary from person to person, making individualized approaches important. A low FODMAP diet, when followed under the guidance of a RD, can help identify which foods worsen your SIBO symptoms and assist in achieving better symptom control.

What fruit is good for SIBO?

Low FODMAP fruits can help manage SIBO symptoms. These include strawberries, blueberries, cantaloupe, honeydew, kiwi, oranges, pineapple, and rhubarb. 

What are the worst foods for SIBO?

The worst foods for SIBO vary from person to person. In general, it’s best to avoid highly processed foods, dairy products, high-fat foods, and food and drinks that are high in sugar—alongside any other foods that trigger your symptoms personally. 

What diets are recommended for SIBO?

One of the most effective diets for treating SIBO is the low FODMAP diet. This temporary elimination diet helps identify any groups of carbohydrates that trigger SIBO symptoms. Once identified, you can avoid these triggers, which may resolve SIBO symptoms and prevent future symptom flare-ups. 

Can you prevent SIBO?

It’s not possible to 100% prevent SIBO. If you do experience SIBO, however, it’s possible to prevent future flare-ups. Typically, this is done through short-term antibiotics use and long-term nutritional and lifestyle adjustments. These adjustments vary from person to person, and working with GI specialists can help identify the changes you should make. 

Can you cure SIBO?

Antibiotics can “cure” SIBO in the short-term. However, to eliminate SIBO long-term, you have to address any lifestyle or nutritional choices that are causing symptoms. To cure SIBO for good, a mix of antibiotics and addressing underlying causes is often employed. 

How long should I do a SIBO diet?

One of the most common SIBO diets, the low FODMAP diet, is temporary. With this diet, someone eliminates all foods containing FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) for two to six weeks. Over the next six to eight weeks, they introduce those foods, noticing which trigger symptoms and which don’t. Those that trigger symptoms are avoided moving forward. 

Final takeaways

“SIBO can be successfully treated and eradicated, though there is risk of recurrence,” concludes Voicechovski, “A GI-focused care team can help individuals with a history of SIBO better understand and address their risk factors to decrease the chance of recurrence.” 

If looking for a GI-focused care team, consider signing up for Oshi Health. Our specialists take a whole-person approach to SIBO, which results in 87% of our patients reporting an improved quality of life in less than three months.