{"id":43,"date":"2026-02-28T08:30:00","date_gmt":"2026-02-28T08:30:00","guid":{"rendered":"https:\/\/regenerated.health\/sibo-diet\/"},"modified":"2026-03-30T13:00:29","modified_gmt":"2026-03-30T13:00:29","slug":"sibo-diet","status":"publish","type":"post","link":"https:\/\/regenerated.com\/blog\/sibo-diet\/","title":{"rendered":"The SIBO Diet: What to Eat, What to Avoid, and How to Heal"},"content":{"rendered":"\n\n\n\n\n\n\n\n

If you’ve been diagnosed with SIBO (small intestinal bacterial overgrowth), the first question most people ask is: “What can I eat?” The answer is more complicated than it should be, because the internet is full of contradictory advice, restrictive food lists, and dietary approaches that range from evidence-based to completely anecdotal.<\/p>\n\n

Here’s the reality. Diet alone doesn’t cure SIBO. No dietary approach will eradicate the bacterial or archaeal overgrowth in your small intestine by itself. What diet can<\/em> do is reduce the symptoms (bloating, gas, pain, diarrhea, constipation) significantly while you’re undergoing treatment, and it can help prevent relapse after treatment succeeds.<\/p>\n\n

This guide covers the four main SIBO dietary approaches, explains which one may work best for your specific SIBO type, and provides practical food lists you can actually use.<\/p>\n\n

Understanding Your SIBO Type Matters for Diet<\/h2>\n\n

Not all SIBO is the same. The type of organisms overgrown in your small intestine determines your symptoms and influences which dietary approach will work best. There are three main types, identified through breath testing.<\/p>\n\n

Hydrogen-Dominant SIBO<\/h3>\n\n

Bacteria in the small intestine ferment carbohydrates and produce excess hydrogen gas. The elevated hydrogen increases the frequency of intestinal contractions, speeding up transit time. The result: bloating, gas, abdominal pain, and diarrhea. This is the most common SIBO type.<\/p>\n\n

Methane-Dominant SIBO (IMO)<\/h3>\n\n

Technically reclassified as Intestinal Methanogen Overgrowth (IMO), this type involves archaea (not bacteria) that consume hydrogen and produce methane. Methane slows intestinal motility, which is why the dominant symptom is constipation rather than diarrhea, often accompanied by severe bloating. Methane producers are archaea, not bacteria, which is why some antibiotics used for hydrogen-dominant SIBO don’t work as well for this type.<\/p>\n\n

Hydrogen Sulfide SIBO<\/h3>\n\n

The newest recognized type. Certain bacteria consume hydrogen and produce hydrogen sulfide gas, which has a characteristic rotten-egg smell. Symptoms often include diarrhea, foul-smelling gas, fatigue, and brain fog<\/a>. Testing for this type is newer and less widely available (the trio-smart breath test measures all three gases).<\/p>\n\n

\nWhy type matters for diet:<\/strong> The organisms producing each gas feed on slightly different substrates. Hydrogen-producing bacteria thrive on fermentable carbohydrates (FODMAPs). Methane-producing archaea feed on the hydrogen produced by those bacteria. Hydrogen sulfide producers have an affinity for sulfur-containing foods. Tailoring your diet to your specific type makes it more effective and less needlessly restrictive.\n<\/div>\n\n

The Four SIBO Diet Approaches Compared<\/h2>\n\n

1. Low FODMAP Diet<\/h3>\n\n

The most widely recommended starting point. FODMAPs<\/a> (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) are short-chain carbohydrates that are poorly absorbed in the small intestine. When bacteria ferment them, they produce gas, draw water into the intestine, and cause the bloating, pain, and altered bowel habits that define SIBO symptoms.<\/p>\n\n

A Low FODMAP approach reduces these fermentable carbohydrates systematically. It was originally designed for IBS but is widely applied to SIBO because the symptom overlap is significant (in fact, research suggests a large percentage of IBS cases may actually be undiagnosed SIBO).<\/p>\n\n

Strengths:<\/strong> The most researched dietary approach for functional GI symptoms. Symptom reduction rates of 50-80% in IBS studies. Clear food lists and portion guides available (the Monash University FODMAP app is the gold standard). Structured elimination and reintroduction phases help identify personal triggers.<\/p>\n\n

Limitations:<\/strong> Designed for IBS, not specifically SIBO. Long-term strict adherence may reduce beneficial bacterial diversity. Evidence specifically for SIBO outcomes is still limited. Doesn’t address the underlying overgrowth.<\/p>\n\n

2. SIBO Biphasic Diet<\/h3>\n\n

Developed by Dr. Nirala Jacobi, the Biphasic Diet was designed specifically for SIBO patients. It combines elements of Low FODMAP with additional restrictions on starches and fibers that can feed small intestinal bacteria.<\/p>\n\n

Phase 1 (Reduce and Repair) is more restrictive, aiming to lower the bacterial load by severely limiting fermentable substrates. Phase 2 (Remove and Restore) gradually reintroduces foods as antimicrobial or antibiotic treatment progresses.<\/p>\n\n

Strengths:<\/strong> Designed specifically for SIBO (not adapted from an IBS protocol). Phased approach reduces restriction over time. Integrates with treatment protocols rather than being standalone.<\/p>\n\n

Limitations:<\/strong> Limited published clinical research compared to Low FODMAP. More restrictive than necessary for some patients, especially in Phase 1. Requires guidance from a practitioner familiar with the protocol.<\/p>\n\n

3. Specific Carbohydrate Diet (SCD)<\/h3>\n\n

Originally developed for inflammatory bowel disease, the SCD eliminates all complex carbohydrates (disaccharides and polysaccharides), allowing only monosaccharides (simple sugars). The theory is that complex carbohydrates feed bacterial overgrowth while simple sugars are absorbed quickly in the upper small intestine before bacteria can ferment them.<\/p>\n\n

Strengths:<\/strong> Strong theoretical basis for starving bacterial overgrowth. Some clinical evidence for IBD. Allows honey, ripe fruit, and certain yogurts that other SIBO diets restrict.<\/p>\n\n

Limitations:<\/strong> No published clinical studies specifically for SIBO. Very restrictive (eliminates all grains, most dairy, potatoes, and sugar). Difficult to maintain long-term. May be unnecessarily restrictive for patients who tolerate some complex carbohydrates.<\/p>\n\n

4. Elemental Diet<\/h3>\n\n

The nuclear option. An elemental diet consists entirely of pre-digested nutrients: amino acids, simple sugars, and fats. These nutrients are absorbed in the very first part of the small intestine, leaving essentially nothing for bacteria further down to ferment. It is the only dietary approach with direct published evidence for eradicating SIBO, not just managing symptoms.<\/p>\n\n

\n
80%<\/div>\n
of SIBO patients on a two-week elemental diet normalized their breath tests in a published study by Dr. Mark Pimentel’s team<\/div>\n<\/div>\n\n

Strengths:<\/strong> The strongest evidence base of any dietary approach for SIBO. Can be used as a primary treatment (not just symptom management). 80% normalization rate in the original Pimentel study, with 65% reporting significant symptom improvement.<\/p>\n\n

Limitations:<\/strong> Extremely difficult to follow. You eat nothing but the elemental formula for 2-3 weeks. It’s essentially a liquid-only diet that tastes mediocre at best. Expensive ($200-400+ for a full course). Not suitable for people with eating disorders or severe caloric restriction issues. Should only be done under clinical supervision.<\/p>\n\n\n
Diet<\/th>SIBO-Specific Evidence<\/th>Restrictiveness<\/th>Best For<\/th><\/tr>\n
Low FODMAP<\/td>Indirect (IBS studies)<\/td>Moderate<\/td>Starting point; hydrogen-dominant SIBO<\/td><\/tr>\n
Biphasic<\/td>Designed for SIBO, limited published data<\/td>High (Phase 1), Moderate (Phase 2)<\/td>Alongside antimicrobial treatment<\/td><\/tr>\n
SCD<\/td>None specific to SIBO<\/td>Very High<\/td>Patients who also have IBD<\/td><\/tr>\n
Elemental<\/td>Strong (direct SIBO study)<\/td>Extreme<\/td>Treatment-resistant SIBO; short-term only<\/td><\/tr>\n<\/table>\n\n

SIBO Food List: What to Eat and What to Avoid<\/h2>\n\n

This food list is based primarily on the Low FODMAP framework with additional considerations for SIBO. It’s a starting point. Individual tolerance varies significantly, and keeping a food journal is one of the most effective tools for figuring out your personal triggers.<\/p>\n\n

Proteins (Generally Well Tolerated)<\/h3>\n\n

Eat freely:<\/span> Chicken, turkey, beef, lamb, pork, fish (all varieties), shellfish, eggs, firm tofu, tempeh (small amounts).<\/p>\n\n

Caution:<\/span> Processed meats with garlic or onion seasoning (check ingredients). Protein powders with added inulin or FOS (common prebiotics that feed bacteria).<\/p>\n\n

Avoid:<\/span> Legume-based proteins (lentils, chickpeas, black beans) during the elimination phase. These are high in galacto-oligosaccharides, one of the most fermentable FODMAP categories.<\/p>\n\n

Grains and Starches<\/h3>\n\n

Eat freely:<\/span> White rice, basmati rice, rice noodles, oats (plain), quinoa, buckwheat, corn tortillas, millet, potatoes (regular and sweet in moderate portions).<\/p>\n\n

Avoid:<\/span> Wheat, rye, barley, spelt, and products made from them (bread, pasta, couscous, most crackers). These contain fructans, a FODMAP category that strongly feeds hydrogen-producing bacteria. Gluten-free substitutes are generally acceptable, but check labels for added inulin or chicory root fiber.<\/p>\n\n

Vegetables<\/h3>\n\n

Eat freely:<\/span> Zucchini, carrots, cucumber, bell peppers, lettuce and leafy greens, green beans (small portions), tomatoes, eggplant, ginger, bok choy, chives, parsnip, pumpkin, bamboo shoots, bean sprouts.<\/p>\n\n

Caution:<\/span> Broccoli and cauliflower (small portions may be tolerated). Celery and corn (moderate portions). Butternut squash (higher FODMAP in large servings).<\/p>\n\n

Avoid:<\/span> Garlic and onion (the two biggest FODMAP triggers in the vegetable category). Mushrooms. Artichokes. Asparagus in large amounts. Cauliflower in large amounts. Brussels sprouts. Snow peas and sugar snap peas.<\/p>\n\n

\nThe garlic and onion problem:<\/strong> These two ingredients are in nearly everything: sauces, dressings, broths, seasonings, and restaurant food. They are also among the highest-FODMAP foods. The good news is that garlic-infused oil (where the garlic is removed after infusing) is Low FODMAP because the fructans are water-soluble, not fat-soluble. This gives you the garlic flavor without the FODMAP load. Asafoetida (hing) spice is another garlic\/onion substitute used widely in Indian cooking.\n<\/div>\n\n

Fruits<\/h3>\n\n

Eat freely:<\/span> Blueberries, strawberries, raspberries, grapes, oranges, kiwi, pineapple, cantaloupe, honeydew, banana (firm, not overripe).<\/p>\n\n

Caution:<\/span> Overripe bananas (higher fructan content). Avocado (Low FODMAP in small portions, but high FODMAP in larger servings).<\/p>\n\n

Avoid:<\/span> Apples, pears, watermelon, mango, cherries, peaches, plums, dried fruit. These are high in excess fructose or sorbitol, both of which are rapidly fermented.<\/p>\n\n

Dairy<\/h3>\n\n

Eat freely:<\/span> Lactose-free milk, hard cheeses (cheddar, parmesan, Swiss), butter, ghee. Hard cheeses are naturally very low in lactose because the aging process breaks it down.<\/p>\n\n

Avoid:<\/span> Regular milk, soft cheeses (ricotta, cottage cheese), ice cream, yogurt (unless lactose-free). Lactose is a disaccharide that bacteria ferment readily.<\/p>\n\n

Nuts and Seeds<\/h3>\n\n

Eat freely:<\/span> Macadamias, walnuts (limited), pecans, pumpkin seeds, sunflower seeds, peanuts (technically a legume but generally tolerated).<\/p>\n\n

Avoid:<\/span> Cashews and pistachios (high FODMAP). Almonds in large quantities.<\/p>\n\n

Fats and Oils<\/h3>\n\n

Eat freely:<\/span> Olive oil, coconut oil, avocado oil, butter, ghee. Fats are not fermented by bacteria and don’t contribute to SIBO symptoms.<\/p>\n\n

Special Considerations by SIBO Type<\/h2>\n\n

Methane-Dominant (IMO): Additional Restrictions<\/h3>\n\n

Methane-producing archaea consume hydrogen gas, so they’re indirectly fed by the same foods that feed hydrogen-producing bacteria. But they’re also particularly responsive to resistant starches and fiber. For methane-dominant SIBO, consider further reducing starchy vegetables (potatoes, sweet potatoes, corn) and high-fiber foods during the treatment phase. Some practitioners recommend a more meat-and-vegetable-heavy approach for methane cases.<\/p>\n\n

Hydrogen Sulfide: Low-Sulfur Modifications<\/h3>\n\n

Hydrogen sulfide-producing bacteria have a preference for sulfur-containing amino acids and foods. If your breath test shows elevated hydrogen sulfide (or if your symptoms include foul-smelling gas), consider limiting high-sulfur foods: cruciferous vegetables (broccoli, cabbage, kale, Brussels sprouts), alliums (garlic, onion, leeks), eggs (especially the yolks), red meat, dairy, wine, and dried fruits preserved with sulfites.<\/p>\n\n

This makes an already restrictive diet even more challenging, which is why working with a SIBO-knowledgeable dietitian is particularly important for hydrogen sulfide cases.<\/p>\n\n

How to Use This Diet Alongside Treatment<\/h2>\n\n

Diet is most effective as a companion to treatment, not a replacement for it. The standard treatment sequence looks something like this.<\/p>\n\n

During the preparation phase (1-2 weeks before treatment), begin your chosen dietary approach to reduce symptoms and lower the bacterial load heading into treatment. During the treatment phase (2-4 weeks of antibiotics or herbal antimicrobials), maintain the diet strictly. This starves the bacteria while the antimicrobials kill them, creating a synergistic effect. During the reintroduction phase (after treatment and a negative breath test), gradually reintroduce restricted foods one at a time, every 3-5 days. Keep a food journal. Some foods that caused symptoms before treatment will be tolerated now. Others may still be problematic. During the maintenance phase (ongoing), most people don’t need to stay on a strict SIBO diet indefinitely. The goal is to find your personal threshold: the least restrictive diet that keeps symptoms manageable while supporting a healthy, diverse microbiome.<\/p>\n\n\n

Related Reading<\/h2>\n\n\n\n