If you suffer from small intestinal bacterial overgrowth (SIBO) symptoms, you are not alone. The condition is surprisingly common, affecting nearly 17% of people with inactive Crohn’s disease, 13% of people with celiac disease, and 67% of people with irritable bowel syndrome (IBS).
Antibiotics are considered the gold standard for SIBO treatment. Yet, these drugs come with side effects and may even worsen or cause new bouts of SIBO when used in the long term.
People searching for a more natural way to improve their symptoms could consider herbal antimicrobials and diets for SIBO. The best diet for SIBO varies from person to person, but some have more evidence backing their benefits than others.
This is the ultimate guide to SIBO diets. Learn your options and discover how Revolution Gut Health can help you customize the perfect diet plan for your symptoms and goals.
What Is the Best Diet for SIBO?
The best diet for SIBO depends on the individual. People respond differently to the same diet because their needs differ. Factors like weight, height, genetics, food allergies, underlying health conditions, and personal goals also affect how someone’s body responds to a particular diet.
Moreover, there are different types of SIBO, each requiring a distinct approach to diet. Making matters worse, two people with the same type(s) of SIBO may respond similarly to a similar diet plan, but only sometimes.
Finding the proper diet for one’s SIBO type and symptoms takes a little trial and error. People can experiment with various SIBO diets and determine which is best for their unique symptoms, lifestyle, and health.
How Food and Diet Impact SIBO
SIBO happens from an overgrowth of bacteria in the small intestine. Improving SIBO involves killing off the overgrowth and restoring the balance of ‘good’ and ‘bad’ bacteria in the gut.
One way to kill off bacteria is to starve them of their food of choice- fermentable carbohydrates. Fermentable carbohydrates include the fiber and starch we ingest through our diets.
Eating a low-fiber diet means gut bacteria can’t access these fermentable carbs. Then, they will also ferment amino acids, the building blocks of proteins, and simple sugars, the building blocks of carbohydrates.
Some diets aim to starve gut bacteria from these fuel sources. They may encourage extended chewing or liquid diets to reduce the amount of undigested food that ends up in the small intestine and feeds overgrowth.
Once the overgrowth is addressed, the proper diet and supplements can also help heal the gut lining, restore beneficial bacteria, and prevent harmful bacteria from migrating from the large intestine to the small bowel.
General Foods to Avoid With SIBO
Understanding what fuels gut bacteria overgrowth in SIBO can help people identify which foods to cut out. For example, someone may consider choosing complex over simple carbohydrates and lowering their overall carbohydrate intake.
People with SIBO symptoms can also consider cutting out foods that are difficult for the digestive system to process. Foods that are hard on digestion include but are not limited to:
- Fried foods
- Processed and artificial sugars
- Dairy products
- Alcohol
- Seed oils
Importantly, diets for SIBO are not meant to last forever. They help manage symptoms in the short term but may worsen digestive symptoms in the long term.
Low-FODMAP Diet for SIBO
The Low FODMAP Diet focuses on cutting out specific types of carbohydrates: fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. The small intestine does poorly in absorbing the nutrients from these sugars.
People who ingest high amounts of FODMAPs may experience uncomfortable digestive symptoms, whether they have SIBO or not. These symptoms may include stomach cramps, diarrhea, constipation, bloating, and gas.
The Low FODMAP Diet goes about supporting these symptoms in a stepwise fashion. First, dieters stop eating high-FODMAP ingredients. Then, they slowly re-introduce ingredients to determine which ones are causing their symptoms.
Foods to Avoid
During the elimination phase (e.g., when someone stops eating high-FODMAP foods entirely), experts suggest cutting out certain foods and ingredients. The following are high in FODMAPs and may be eliminated during the first phase of the diet:
- Dairy products
- Wheat-based products
- Beans and lentils
- Certain vegetables, including artichokes, asparagus, onions, and garlic
- Certain fruits, including apples, cherries, pears, and peaches
Experts recommend cutting out these items for at least two or up to six weeks before entering the re-introduction phase. During re-introduction, individuals may add one high-FODMAP food every three days.
If a food increases one’s digestive symptoms upon re-introduction, that food should be avoided in the long term.
Foods to Include
During all phases of the Low FODMAP Diet, people should focus on low-FODMAP foods and ingredients. The best items to reach for during the elimination and re-introduction phases include:
- Eggs
- Meat products
- Certain cheeses, including cheddar, feta, and brie
- Almond milk
- Grains, including rice, quinoa, and oats
- Certain vegetables, including eggplant, potatoes, tomatoes, cucumbers, and zucchini
- Certain fruits, including grapes, oranges, strawberries, blueberries, and pineapples
People can also eat high-FODMAP foods that are re-introduced to their diet and do not cause uncomfortable digestive systems.
The Specific Carbohydrate Diet for SIBO
Like the Low FODMAP Diet, the Specific Carbohydrate Diet (SCD) is an elimination diet. It involves eliminating certain ingredients from one’s diet before re-introducing them one at a time. The ultimate goal is to reduce digestive system inflammation to decrease SIBO-related symptoms.
The difference is that the SCD specifically targets complex carbohydrates ingested from certain sources. It is virtually identical to a gluten-free diet. The SCD was originally developed to support celiac disease and gluten sensitivities.
This diet is highly restrictive. When trying the SCD for SIBO, individuals may need to incorporate supplements to prevent Vitamin D and folic acid deficiencies.
Foods to Avoid
The Specific Carbohydrate Diet requires completely cutting out grains. Remember that grains include not only wheat-based products like bread, pasta, and baked goods but also corn, barley, oats, and rice. Additionally, when trying the SCD, avoid highly processed foods and ingredients rich in sugar and lactose.
Here is the full list of foods to avoid on the SCD:
- Sugar, molasses, maple syrup, sucrose, high-fructose corn syrup, and other processed sugars
- Starchy tubers and root tubers like potatoes, sweet potatoes, and turnips
- Milk and milk products like yogurt, cream, sour cream, ice cream, and certain cheeses
- Candy, chocolates, and other sweets that contain fructooligosaccharides
- Canned and processed meats
- Canola oil
- Mayonnaise with additives
- Canned vegetables with added ingredients
- Seaweed
Though the SCD is meant to be a temporary fix, some people follow it for life. Others wait until they are symptom-free for at least one year before progressively re-introducing foods. Another solution is to move from the SCD to a modified specific carbohydrate diet.
Foods to Include
People following the Specific Carbohydrate Diet can still get the majority of their nutrients from allowed foods, such as:
- Additive-free meats, poultry, and fish
- Eggs
- Certain legumes, including navy beans, lentils, peas, and lima beans
- Certain unroasted, unshelled nuts, including cashews and peanuts, and all-natural peanut butter
- Certain cheeses, including cheddar, Colby jack, swiss, and dry curd cottage cheese
- Homemade yogurt, but only if it is fermented for at least 24 hours
- Fresh, frozen, raw, and cooked vegetables
- Fresh, raw, cooked, frozen, and dried fruits
- Nut flours
- Honey
- Oils
- Tea and coffee
- Mustard
- Cider
- White vinegar
- Fruit and vegetable juices, but only if they have no added sugars
People worried about nutritional deficiencies while following the SCD or modified carbohydrate diet should consult a doctor about the right supplements for their unique needs.
Low Fermentation/Cedars Sinai Diet
Not all carbohydrates survive the digestive system long enough to feed overgrown bacteria in the small intestine. Others do survive to reach the gut, feeding the overgrowth causing someone’s SIBO symptoms.
The Low Fermentation Diet aims to starve the gut of these hardy carbs. Dr. Mark Pimentel, the SIBO expert and executive director of the Medically Associated Science and Technology Program at Cedars-Sinai Hospital, designed the Cedars Sinai Diet.
Think of the Low Fermentation Diet as a cross between the Low FODMAP Diet and a type of fasting known as meal spacing. Meal spacing encourages people to space out meals by 4-5 hours, avoid eating between them, and not eat before bed.
Foods to Avoid
The Cedars Sinai Diet is the least restrictive of those we’ve discussed so far. It does not require eliminating entire food groups. Instead, certain items in specific food groups are off-limits.
Foods to avoid on the Low Fermentation Diet for SIBO include:
- Non-digestible sugars, including fructose, lactose, sucralose, sorbitol, xylitol, lactulose, and lactitol
- Certain dairy products, including yogurt, non-lactaid milk, and cheese
- Certain breads, including whole wheat and multigrain
- Added fibers, including those from fiber supplements, fortified cereals, and oatmeal
- Protein powders sweetened with non-digestible sugars
- Sodas, including diet sodas sweetened with non-digestible sugars
- Certain vegetables, including beans, chickpeas, legumes, cabbage, Brussels sprouts, broccoli, cauliflower, and leafy greens
- Certain fruits, including apples, pears, and bananas
Additionally, limit snacks between meals and do not eat before bed to give the digestive system time to cleanse itself of the old food and make room for the next meal.
Foods to Include
Lactose-free ice cream and other dairy products, hard cheeses, and oil-based sweets are okay on the Cedars Sinai Diet in moderation. Dieters can enjoy the following foods at any time:
- Lactaid milk
- Sweets containing sucrose, glucose, and NutraSweet
- Simple carbohydrates, including rice, potatoes, sweet potatoes, white bread, pasta, and cream of wheat
- Tubers and root vegetables, including onions, garlic, beets, carrots, and turnips
- Fruiting vegetables, including peppers, tomatoes, cucumbers, zucchini, squash, eggplants, and peas
- All fruits except for the ones listed above
- All protein sources
- All fatty foods
- All nuts
The Low Fermentation Diet can be a temporary or long-term solution.
Carnivore Diet for SIBO
The diets we’ve discussed so far help to manage, not treat, SIBO symptoms. The Carnivore Diet for SIBO is different, as one study has shown it can cure SIBO.
The 2022 study investigated the effects of this carbohydrate-free diet on six people who tested positive for hydrogen SIBO. Five participants completed the six-week diet plan and tested negative for SIBO at the end of the period.
One patient was only able to complete two weeks of the diet but still tested negative for SIBO after only two weeks. However, this participant is a cautionary tale for the Carnivore Diet’s highly restrictive nature. Cation must also be taken as this sample size is small; further research is needed.
Foods to Avoid
The Carnivore Diet does not allow carbohydrates or fiber. The goal is to eliminate gut bacteria’s food of choice to starve them off while feeding the body the essential nutrients it needs to survive.
Foods to avoid on this SIBO diet include:
- All grains, nuts, and seeds
- All fruits and vegetables
- All legumes
- High-lactose dairy products
Though relatively simple to remember, this diet is challenging to follow. Dieters should only try this option under a doctor’s supervision to prevent nutritional deficiencies.
Foods to Include
The Carnivore Diet only allows animal and some animal-derived products. Foods to include while following this diet include:
- Meat
- Fish
- Eggs
Some low-lactose dairy products are also allowed. For example, dieters can enjoy butter and hard cheeses like parmesan, pecorino, gruyere, and cheddar.
Low Sulfur Diet
There are many low-sulfur diets, all with the same goal of reducing someone’s consumption of sulfur-containing foods. Some are stricter than others, and one requires dieters to track their daily sulfur consumption.
The simplest version of this diet is known as the Hydrogen Sulfide Diet. It is specifically designed for people with a certain type of SIBO: Hydrogen Sulfide SIBO. Hydrogen Sulfide SIBO features an overgrowth of H2S-producing bacteria in the small intestine.
Sulfur feeds these bacteria. Eliminating their food source may help with Hydrogen Sulfide symptoms. Individuals can follow a low-sulfur eating plan like the Hydrogen Sulfide Diet.
Foods to Avoid
Dieters should not consume foods high in sulfur while on this diet. High-sulfur foods to eliminate or eat in moderation include:
- Sulfur-containing supplements
- Beer, wine, and cider
- Apple, tomato, and grape juice
- Dairy products
- Dried fruits
- Certain vegetables, including asparagus, broccoli, Brussels sprouts, red cabbage, leeks, onions, radishes, turnips, and watercress
- Certain proteins, including red meat, fish, eggs, pork, and white poultry meat
- Soy and soybeans
- Certain nuts and seeds, including Brazil nuts, almonds, sesame seeds, and peanuts
- Mustard
- Certain grains, including barley, oats, and wheat
People who drink well water should also consider switching to bottled. Well water is naturally high in sulfur.
Foods to Include
Dieters can eat small, 3-4 ounce portions of animal proteins lower in sulfur, especially dark meat, poultry, and fish. Other low-sulfur items to include during a Hydrogen Sulfur Diet for SIBO are:
- Plant-based protein sources, including beans, lentils, and legumes
- Certain vegetables, including squash, carrots, celery, mushrooms, bell peppers, cucumbers, eggplant, spinach, artichokes, and corn
- Certain fruits, including cantaloupe, watermelon, grapefruit, and apples
- Certain grains, including rice, potatoes, and sweet potatoes
- Low-sulfur nuts and seeds
The body needs small amounts of sulfur to survive. Following this diet plan allows people to consume just enough of this essential mineral without the associated digestive symptoms.
Biphasic Diet for SIBO
The Biphasic Diet for SIBO crosses the Low-FODMAP Diet and the Specific Carbohydrate Diet (SCD). It is an elimination diet, meaning dieters start by eliminating certain foods before re-introducing some. In this case, foods are not re-introduced one at a time.
The first phase encourages people to enjoy some foods and eliminate or limit others to alleviate symptoms. The second phase is less restrictive and aims to remove the overgrowth and promote motility. Each phase lasts 4-6 weeks.
Starches and fiber are the primary targets of this diet. The idea is to starve gut bacteria of their preferred food source. During phase 2, dieters should also take herbal antimicrobials to encourage SIBO die-off.
Foods to Avoid
Phase 1 of the Biphasic Diet divides foods into three categories: foods to eat, foods to limit, and foods to avoid. The foods to avoid are the same as those listed above under the Low-FODMAP and Specific Carbohydrate Diets.
Experts recommend eliminating ‘foods to limit’ for the first few weeks before gradually re-introducing them once symptoms resolve. Foods to limit: rice, quinoa, and all fruits except lemons and limes. Dieters should also avoid having more than one serving of the following vegetables per day:
- Asparagus
- Artichoke
- Beetroot
- Broccoli
- Brussels sprouts
- Cabbage
- Celery
- Green peas
- Pumpkin
- Snow peas
- Spinach
- Zucchini
Phase 2 encourages dieters to continue restricting items in the ‘foods to avoid’ category while gradually re-introducing the ‘foods to limit’ group.
Foods to Include
The Biphasic Diet allows the following foods during the first and second phases:
- Meat, fish, and chicken
- Eggs
- Certain vegetables, including alfalfa sprouts, bamboo shoots, bok choy, carrots, cucumbers, eggplant, ginger, kale, lettuce, olives, and tomatoes
- Stevia
- Coconut oil, flaxseed oil, ghee, grapeseed oil, MCT oil, olive oil, pumpkin seed oil, sesame oil, sunflower oil, and walnut oil
- Fresh and dried herbs
- Sugar-free mayonnaise, garlic-free mustard, tabasco, and wasabi
- Vinegar
During phase 2 of the diet, people can also eat items from the ‘foods to limit’ mentioned above.
Paleo Diet for SIBO
The Paleo Diet is a popular weight loss diet that may also benefit SIBO. The diet mimics what our hunter-gatherer ancestors ate- a diet rich in whole foods.
There are various types of paleo diets, but most aim to reduce the consumption of highly processed foods that can be hard on digestion. Dieters are also encouraged to limit their consumption of grain, dairy, and legumes.
Of all the diets listed so far, the Paleo Diet is relatively non-restrictive. The bad news is that there is no research backing this diet’s effects on SIBO symptoms, though it should help since it limits carbohydrate intake.
Foods to Avoid
Foods to avoid on the Paleo Diet include:
- Processed foods
- Refined sugars and artificial sweeteners
- Cereal grains
- Legumes, including peanuts, beans, lentils, and soy products
- Sodas and other sweetened beverages
- Salt
- Refined oils
In addition to improving SIBO, reducing one’s consumption of these items can also lower the risk of obesity, heart disease, and other chronic diseases.
Foods to Include
Here are the top foods to include on the Paleo Diet:
- Grass-fed or wild-caught meat, poultry, and fish
- Eggs
- Fruits and vegetables
- Healthy oils, including avocado oil, coconut oil, and olive oil
- Nuts and seeds
Focusing on these foods is not just helpful for SIBO. Eating a whole-food diet may also encourage weight loss.
SIBO-Specific Diet for SIBO
Like the Biphasic Diet, the SIBO-Specific Diet combines the Low-FODMAP and Specific Carbohydrate Diets. It is unique in that the diet divides fermentable carbohydrates into three categories: low, moderate, and high FODMAP and fermentable.
A dieter may be able to eat items from all but one of these groups, depending on the severity of their SIBO symptoms. For instance, someone with mild symptoms might only avoid the fermentable category, while someone with more severe symptoms would only stick with foods in the low-FODMAP group.
The only evidence that this diet works for SIBO is anecdotal. However, the SIBO-Specific Diet was designed by Naturopathic Doctor Allison Siebecker, the former medical director of the SIBO Center for Digestive Health.
Foods to Avoid
Foods to eliminate on the SIBO-Specific Diet are called ‘illegal.’ They include:
- Certain vegetables, including corn, okra, bean sprouts, turnips, water chestnuts, and yucca root
- All canned vegetables
- Certain starches, including potatoes, sweet potatoes, yams, and taro
- Seaweed
- Starch powders, including arrowroot, corn starch, potato starch, rice starch, and tapioca starch
- Plantains
- Certain beans, including cannellini, butter, fava, pinto, garbanzo, and soybeans
- Chia seeds and seed flour
- Certain dairy products, including cheese, kefir, cream, milk, sour cream, and yogurt
- Processed meats
- Certain sweeteners
- Soda
- Soybean oil
These ingredients are highly fermentable by gut bacteria and should be avoided while on the diet.
Foods to Include
Foods to include on the SIBO-Specific Diet are categorized as ‘legal.’ However, they are further divided based on their FODMAP content. The lowest FODMAP and most minor fermentable group of foods include:
- Most fats
- Certain sweeteners, including glucose, honey, pure saccharine, and Stevia
- Most proteins
- Certain dairy products, including butter, aged cheeses, ghee, and homemade sour cream and yogurt
- Most nuts and seeds
- Lentils and lima beans
- Low-FODMAP fruits and vegetables
Other foods may be allowed depending on how many categories a dieter can eat from.
Low-Histamine Diet for SIBO
Many people with SIBO also have a dietary histamine intolerance. Many experts believe that histamine intolerance originates in the gut, but whether SIBO or histamine intolerance comes first is unclear.
People with SIBO symptoms and signs of histamine intolerance may benefit from a Low Histamine Diet. Signs of histamine intolerance include gastrointestinal symptoms, flushing, congestion, and dizziness.
The Low Histamine Diet relies on the fact that some foods are lower in histamine than others. Cutting out high-histamine foods may benefit their SIBO and histamine intolerance symptoms.
Foods to Avoid
The Low Histamine Diet encourages people to avoid high-histamine foods. High-histamine foods are typically fermented, aged, or processed and include:
- Certain dairy products, including aged cheese, yogurt, sour cream, and buttermilk
- Fermented ingredients, including kefir, sauerkraut, kimchi, fermented pickles, and kombucha
- Cured meats and fish
- Tempeh, miso, soy sauce, and natto
- Fermented grains
- Certain vegetables, including tomatoes, eggplant, and spinach
- Vinegar
- Ketchup
- Alcohol
It is possible to turn this diet into an elimination one. Dieters can re-introduce these items individually to see if a specific food is causing their symptoms.
Foods to Include
As long as dieters avoid the above foods, there is no limit to what they can eat. Focus on the following tips for best results:
- Always use fresh ingredients
- Cook all meals at home
- Eat foods in their original, whole form
Experts do not recommend this diet for longer than four weeks. Individuals should also consult a doctor about supplements, as the Low Histamine Diet’s restrictive nature could cause nutrient deficiencies.
GAPS Diet for SIBO
The GAPS Diet, or the Gut and Psychology Syndrome Diet, has a unique value proposition. It aims to help with not only gut health symptoms but also associated cognitive conditions like autism, ADHD, and dyslexia.
Researchers have uncovered a bi-directional connection between the gut and the brain called the gut-brain axis. The gut-brain axis may explain why mental health can impact the gut, and the gut’s health can lead to mental illnesses like anxiety and depression.
The GAPS Diet is a three-phase process of eliminating, maintaining, and re-introducing certain foods. Dieters should only move to the next phase when they experience reduced symptoms and improved bowel movements.
Foods to Avoid
During the first phase of GAPS, the following food groups should be avoided entirely:
- Grains and refined carbohydrates
- Pasteurized dairy products
- Starchy vegetables
- Packaged or canned foods
The second phase is slightly less restrictive, encouraging dieters to avoid grains, refined carbohydrates, and dairy products.
Foods to Include
During the first phase, dieters should only consume broths, stews, and probiotic foods free from the above ingredients. The second phase of the GAPS Diet allows for the re-introduction of solids, including:
- Hormone-free, grass-fed meats and fish
- Animal fats
- Organic eggs
- Vegetables
- Moderate servings of nuts
- Baked goods made from nut flour
Once someone has experienced normal bowel movements for six months, they can move on to the final phase of the diet. Dieters should re-introduce foods gradually, starting with potatoes and gluten-free grains.
Elemental Diet for SIBO
The Elemental Diet is similar to the Carnivore Diet in that it has been studied as a treatment for SIBO instead of simply managing symptoms. For example, a study of 93 people with SIBO found an 80% success rate with this diet after two weeks and an 85% success rate after three weeks.
This diet works because people with suboptimal gut health may not fully digest their food. The result is undigested food particles making their way to the small intestine, where they feed bacterial overgrowth.
The Elemental SIBO Diet is a liquid diet. It offers the nutrients someone needs to survive, but in a pre-digested form that reduces food for gut bacteria. These bacteria starve and die off, alleviating SIBO symptoms.
Foods to Avoid
Foods to avoid on the Elemental Diet include whole foods, such as:
- Meat, poultry, fish, and processed meats
- Eggs and dairy products
- Fruits and vegetables
- Processed foods
- Coffee and tea
- Alcohol
- Sugar
Consuming these foods while on the Elemental Diet can limit its effectiveness.
Foods to Include
The only foods allowed on the Elemental Diet are meal-replacement drinks. These drinks contain pre-digested nutrients the body and brain need to function optimally.
Unfortunately, the restrictive nature of the Elemental Diet has made it difficult for people to adhere to. Additionally, the diet can be expensive, and there is no alternative way to DIY this diet.
Vegan Diet for SIBO
A vegan diet is free of all animal products. Dieters only eat foods that grow from plants or are made from plant-derived ingredients, including fruits, vegetables, grains, beans, nuts, seeds, and plant-based fats.
There are many types of vegan diets, each with its pros and cons. Science-backed benefits of going vegan, in general, include getting more nutrients, losing weight, and reducing the risk of chronic illnesses.
However, we do not recommend any type of vegan diet for SIBO. These diets are too high in fiber and fermentable carbs. People with SIBO may have trouble digesting these foods at best or experience symptom flare-ups at worst.
Find the Best Diet for Your SIBO Symptoms
The best diet for SIBO depends on the individual, their SIBO type, and any pre-existing health conditions they may have. Finding and sticking to the right SIBO diet plan is easier when you have the help of a trusted gut health expert every step of the way.
Do you need help finding the right diet for your unique SIBO symptoms, goals, and lifestyle? The experts at Revolution Gut Health provide a natural and highly effective approach to supporting SIBO and other gut disorders.
Schedule a consultation with us to learn how we can help you find relief even when other healthcare providers can’t.