Small intestinal bacterial overgrowth (SIBO) happens when bacteria that normally live in your colon migrate into your small intestine and multiply there, where they have no business being in such high numbers. A peer-reviewed review of SIBO explains that the small intestine is normally protected from excessive bacterial colonization by stomach acid, pancreatic enzymes, the intestinal immune system, peristalsis, and the ileocecal valve, and that SIBO develops when one or more of these protective mechanisms break down. Once bacteria take hold in the small intestine, they ferment the carbohydrates you eat before your body can absorb them, producing the hydrogen, methane, or hydrogen sulfide gas responsible for the bloating, excess gas, abdominal pain, and altered bowel habits that define this condition.
It is important to be upfront about something most SIBO diet content glosses over: the same review concludes that the studies evaluating diet as a treatment for SIBO are of low methodological quality, and that there is still not enough scientific evidence to support any single specific diet for treating the condition. The gold-standard treatment remains antibiotics aimed at eradicating the bacterial overgrowth directly. Diet’s real role is supportive: reducing the fermentable fuel available to overgrown bacteria can ease symptoms while you pursue proper treatment, and a structured reintroduction afterward helps you identify which foods you tolerate long term. This grocery list is built around that supportive role rather than overselling diet as a cure.
How Diet Fits Into SIBO Treatment
Bacteria need fermentable carbohydrates to produce gas. Short-chain fermentable carbohydrates, the same compounds tracked in a low FODMAP diet, are rapidly fermented by small intestinal bacteria. Reducing them reduces the fuel available for fermentation and the gas, bloating, and pain that result.
The elemental diet works by starving bacteria almost entirely. The original clinical trial behind this approach found that 80% of patients with SIBO had a normal breath test after 14 days on a liquid, pre-digested elemental formula that requires no digestion and leaves almost nothing behind for bacteria to ferment. This is the most restrictive dietary intervention used for SIBO and is typically reserved for cases that have not responded to other treatments, under medical supervision.
A low FODMAP diet reduces symptoms without necessarily eradicating the overgrowth. A registered clinical trial protocol studying low FODMAP diets in SIBO patients notes that this approach is widely used to reduce bloating and gas, even though its effect on bacterial overgrowth itself, rather than just symptoms, remains an active area of study.
Diet alone is rarely the whole answer. A recent systematic review and meta-analysis found that elemental diets show encouraging breath-test normalization in selected patients and that low FODMAP or low-residue plans are commonly used as maintenance diets after eradication, but cautioned that these dietary strategies still require controlled trials before firm claims about preventing relapse can be made.
SIBO Diet Foods List: What to Buy
Low-FODMAP Proteins (Safest Category Across All Phases)
Protein itself does not feed fermenting bacteria the way carbohydrate does, which makes lean, unprocessed protein one of the most reliably well-tolerated categories at every stage of a SIBO diet.
Best sources:
- Chicken breast and turkey, plain and unmarinated (avoid bottled marinades, which often contain garlic and onion)
- Fresh fish such as salmon, cod, or tilapia
- Eggs
- Firm tofu, in modest portions (fermented soy products like tempeh are higher FODMAP and best limited)
Low-FODMAP Vegetables
Best choices:
- Carrots
- Cucumber and zucchini
- Spinach
- Red bell peppers
- Green beans
- Eggplant
- Lettuce and other leafy salad greens
- Potatoes, white and sweet
Low-FODMAP Fruits, in Modest Portions
Fruit portion size matters as much as fruit choice, since even low-FODMAP fruits can trigger symptoms in larger amounts.
Best choices:
- Firm, slightly underripe bananas
- Blueberries and strawberries
- Grapes
- Oranges
- Kiwi
Low-FODMAP Grains and Starches
- White rice
- Quinoa
- Gluten-free bread, checking the ingredient list for added inulin or chicory root
- Plain polenta or cornmeal
- Oats, in modest portions
Soothing, Gut-Friendly Additions
- Bone broth, easy to digest and gentle on the gut during flares
- Fresh ginger, traditionally used to ease nausea and support digestion
- Peppermint tea, which has antispasmodic properties that may ease cramping and bloating, though it is generally avoided by people who also have acid reflux
- Fresh low-FODMAP herbs such as basil, oregano, thyme, and chives (the green tops only, not the white bulb)
Healthy Fats
- Olive oil
- Macadamia nuts, one of the lower-FODMAP nuts
- Pumpkin seeds
Foods to Avoid With SIBO
High-FODMAP Vegetables
These vegetables are rich in fructans and other fermentable carbohydrates that small intestinal bacteria readily ferment into gas.
Foods to avoid:
- Onion and garlic, including powders and most pre-made sauces and broths
- Leeks and shallots
- Mushrooms
- Cauliflower
- Asparagus
- Artichokes
High-FODMAP Fruits
Foods to avoid:
- Apples and pears
- Watermelon
- Mango
- Dried fruit of any kind
- Stone fruits such as peaches and plums
Legumes and High-Fiber Beans
Legumes are nutritious but rich in fermentable oligosaccharides that are particularly difficult for an overgrown small intestine to handle, which is why they are typically limited during the active symptom-management phase, even though they can often be reintroduced later.
Foods to avoid during active symptoms:
- Chickpeas and hummus
- Lentils
- Kidney beans and most other beans
- Soybeans and edamame
Wheat and High-Fructan Grains
Foods to avoid:
- Wheat bread and wheat pasta
- Rye and barley
- Couscous
Dairy Products Containing Lactose
Foods to avoid or limit:
- Milk
- Soft, fresh cheeses
- Ice cream
- Regular yogurt (lactose-free versions are generally better tolerated)
Sugar Alcohols and High-Fructose Sweeteners
Foods to avoid:
- Sugar-free gum and candy containing sorbitol, mannitol, or xylitol
- Agave syrup and honey
- High-fructose corn syrup-sweetened products
Prebiotic Fibers and Supplements During Active Treatment
This category surprises people, since prebiotic fiber is usually framed as universally healthy. During active SIBO, however, the same fermentable fibers that support a healthy colon can feed the overgrowth in the small intestine, which is why they are typically paused during treatment and reintroduced afterward.
To pause during active treatment:
- Inulin and chicory root, found in many fiber supplements and added to packaged foods
- Fructooligosaccharide (FOS) and galactooligosaccharide (GOS) supplements
SIBO Diet Grocery List by Store Section
This list covers one week for one adult during the active symptom-management phase of a SIBO diet.
Produce
- Carrots (500g)
- Cucumber and zucchini (2 each)
- Spinach (1 bag)
- Red bell peppers (3)
- Green beans (1 bag)
- Eggplant (1)
- Lettuce (1 head)
- Potatoes, white and sweet (4 medium)
- Firm bananas (1 bunch)
- Blueberries and strawberries (1 punnet each)
- Grapes (1 bunch)
- Oranges (4)
- Fresh ginger (1 piece)
- Fresh herbs such as basil and chives (1 bunch each)
Meat, Seafood, and Eggs
- Chicken breast and turkey, unmarinated (600g combined)
- Fresh salmon or cod (2 to 3 portions)
- Eggs (1 dozen)
- Firm tofu, in modest portions (1 block)
Dairy and Alternatives
- Lactose-free milk (1 carton)
- Lactose-free yogurt (1 tub)
- Hard aged cheeses, such as Parmesan, in small amounts if tolerated, since most lactose breaks down during aging
Grains and Pantry
- White rice (1 kg)
- Quinoa (500g)
- Gluten-free bread, checked for added inulin or chicory root (1 loaf)
- Plain polenta or cornmeal (500g)
- Oats, in modest portions (1 container)
- Olive oil (1 bottle)
- Macadamia nuts and pumpkin seeds (150g each)
Frozen
- Frozen blueberries and strawberries (1 bag each)
- Frozen green beans (1 bag)
- Frozen salmon or white fish fillets (1 bag)
Beverages and Broths
- Bone broth, store-bought low-FODMAP or homemade without onion and garlic
- Peppermint tea, if you do not also have acid reflux
- Water, primary beverage
Practical Tips for the SIBO Diet
Get a proper diagnosis and medical treatment before relying on diet alone. Diet can ease symptoms, but the strongest evidence still points to antibiotics or other medical therapies for actually addressing the bacterial overgrowth itself, so work with a gastroenterologist rather than treating diet as a substitute.
Treat a low FODMAP approach as a temporary trial, not a permanent diet. Most practitioners recommend a four-to-six-week low FODMAP trial followed by careful, food-by-food reintroduction, since the diet is restrictive enough that staying on it indefinitely can affect both your gut microbiome diversity and your nutrient intake.
Space meals three to four hours apart. Constant snacking keeps your digestive system in a fed state and interferes with the migrating motor complex, the wave of muscle contractions that sweeps bacteria out of the small intestine between meals.
Be cautious with probiotics and prebiotic fiber during active overgrowth. While these are generally beneficial for gut health, introducing them while bacterial overgrowth is still active can sometimes worsen bloating and gas, so it is often better to wait until after treatment to reintroduce them gradually.
Reintroduce foods one at a time after treatment. Once symptoms have improved, add foods back individually over several days each, prioritizing foods you miss most, so you can identify your genuine long-term triggers rather than staying needlessly restricted.
Keep a symptom journal throughout. SIBO symptoms can be triggered by stress, meal timing, and food all at once, so tracking everything together gives you a clearer picture than tracking food alone.
The Bottom Line
Diet cannot cure SIBO on its own, and the research behind any single SIBO diet remains limited, but reducing fermentable carbohydrates while you pursue proper medical treatment can meaningfully ease bloating, gas, and abdominal pain in the meantime. Build your grocery list around lean proteins, low-FODMAP vegetables and fruits in modest portions, and gut-soothing additions like bone broth and ginger, while limiting high-FODMAP vegetables, legumes, wheat, lactose-containing dairy, and prebiotic fiber supplements during the active phase. Treat this as a temporary, supportive approach alongside medical care rather than a standalone fix, and reintroduce foods deliberately once your symptoms and bacterial overgrowth have actually improved.
Disclaimer: Nutritional data referenced in this article is sourced from USDA FoodData Central. This article is for informational purposes only and does not constitute medical or dietary advice. SIBO should be diagnosed through proper testing and treated under the guidance of a gastroenterologist, since diet alone has limited evidence as a treatment and a restrictive diet maintained too long without supervision can lead to nutrient gaps. Always consult your doctor or a registered dietitian before starting a SIBO elimination diet, particularly an elemental diet.
