Small intestinal bacterial overgrowth (SIBO) is a condition where there's an excessive amount of bacteria in the small intestine. This overgrowth can lead to various uncomfortable symptoms, including bloating, gas, abdominal pain, and altered bowel habits. Research suggests that SIBO may play a significant underlying factor in irritable bowel syndrome (IBS). If you’ve recently been diagnosed with SIBO (Small Intestinal Bacterial Overgrowth) and been asked to follow a specific protocol in an effort to help calm symptoms down-we’ve got you. It is absolutely normal to feel overwhelmed, not knowing where to start. Diet is one of the key factors in managing SIBO symptoms. This article delves into the specifics of a SIBO diet, particularly for methane-dominant SIBO, providing practical guidance and meal plan ideas.
Understanding SIBO and Its Dietary Management
All of us have bacteria in our gut, but most of it is located in our large intestine. Small intestinal bacterial overgrowth (SIBO) happens when there’s a disruption to the normal amount of bacteria found in your small intestine. If you have SIBO, you want to limit or avoid foods that may increase the amount of bacteria in your small intestine. An increase in bacteria can lead to symptoms like bloating and abdominal discomfort, says functional medicine specialist Melissa Young, MD. The purpose of a SIBO diet is to temporarily reduce the amount of fermentable carbohydrates in your diet and help improve your SIBO symptoms. By temporarily reducing or removing fermentable foods that your bacteria love to eat, you reduce the amount of gas they produce, therefore reducing the symptoms you feel while simultaneously treating the overgrowth and healing the gut.
The Challenge of Methane-Dominant SIBO
If you’ve been diagnosed with methane-dominant SIBO (also called intestinal methanogen overgrowth, or IMO) or suspect it might be part of the picture, you’re probably overwhelmed by all the conflicting diet advice. There’s no official, evidence-based methane SIBO diet (methane SIBO is a type of small intestinal bacterial overgrowth) - just a lot of conflicting advice, most of it not written by dietitians. Methane-producing microbes, specifically Methanobrevibacter smithii, don’t actually ferment food. Instead, they feed on the hydrogen gas that other bacteria produce. In nearly every case of methane SIBO, hydrogen-producing bacteria are still present too. You need both types for methane to be made-the hydrogen producers create the gas, and the methane producers convert it.
Methane itself slows down gut motility. That means food and bacteria hang out in the small intestine longer, giving even small amounts of fermentable material more time to cause issues. This is why many people with methane SIBO find themselves stuck. A methane SIBO diet has to go beyond just removing fermentable carbs. Diet is only one piece of the puzzle.
Core Principles of a Methane SIBO Diet
Here's what really works to treat methane SIBO from the root:
Read also: The Carnivore Diet for SIBO
- Reduce available hydrogen by limiting fermentation from carbs and resistant starch: The more you feed those hydrogen producers, the more methane gets made. That’s why this diet focuses on cutting back the types of carbs and fibers that drive fermentation, like FODMAPs and resistant starches, especially the ones that bypass digestion and ferment in the colon.
- Support motility and regular bowel movements: Methane gas slows intestinal transit, and slow motility makes everything worse-more fermentation, more gas, more symptoms. So this diet includes foods and patterns that gently support movement: warm fluids, soluble fiber, consistent rhythms, and avoiding meal patterns that bog things down.
- Reduce pressure, bloating, and trapped gas: The hallmark methane SIBO symptoms often include bloating, fullness, abdominal pain, and that “backed up” sensation that never fully goes away.
- Maintain nutritional adequacy without over-restriction: The methane SIBO diet should still include enough variety to nourish your gut lining, support digestion, and keep your energy up.
These principles are what guide the food choices in a methane SIBO-friendly diet. This isn’t about rigid rules; it’s about being strategic, so meals work with your gut instead of against it.
Dietary Approaches for SIBO
While there isn’t an official “SIBO diet,” your healthcare provider may recommend an eating plan like the following.
Low-FODMAP Diet
“FODMAP” stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. FODMAPs are foods that you may have trouble digesting when you have SIBO. The Low FODMAP diet eliminates foods that ferment and cause digestive discomfort (FODMAPs). The Low FODMAP diet was originally designed to help people with irritable bowel syndrome (IBS) by reducing fermentable carbohydrates-specifically, Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are short-chain carbs that are poorly absorbed in the small intestine and become food for hydrogen-producing gut bacteria. In hydrogen-dominant SIBO, cutting down on these fermentable carbs can significantly reduce symptoms by limiting the fuel source for those bacteria.
A low-FODMAP diet focuses on limiting or eliminating high-FODMAP foods, like beans, lentils and wheat-based snacks. The idea is that avoiding high-FODMAP foods may slow bacterial overgrowth that happens when bacteria feed on these types of foods. Instead, you want to fill your plate with low-FODMAP foods, like proteins, vegetables, fruit, grains and dairy, as well as nuts and seeds, that are less likely to trigger a bacterial growth spurt.
Some foods that are considered low-FODMAP include:
Read also: Phase 1 SIBO Diet
- Fruits like grapes, oranges and strawberries
- Vegetables like carrots, cucumbers and tomatoes
- Nuts and seeds like walnuts and pumpkin seeds
- Dairy alternatives like almond milk and soy milk
- Protein options like eggs and plain, cooked meats, poultry and seafood
- Gluten-free grains like quinoa and oats
“After the initial elimination phase of about three to four weeks while you’re being treated for SIBO, you’ll then slowly reintroduce food from one high-FODMAP group at a time,” says Dr. Young. Following a low-FODMAP diet long term isn’t recommended, as many of these highly fermentable foods feed your gut microbiome.
SIBO Specific Diet
The SIBO Specific Diet is a highly restrictive dietary protocol that merges principles from the Low-FODMAP Diet and the Specific Carbohydrate Diet (SCD). The Specific Carbohydrate Diet is based on the framework and Legal/Illegal List from Elaine Gottschall's book, "Breaking the Vicious Cycle: Intestinal Health Through Diet". This diet allows carbohydrate foods consisting of monosaccharides only and uses recipes made with "legal" ingredients. By removing lactose, complex starches, and fermentable fibers, this diet reduces symptoms and helps calm the gut environment. The SIBO Specific Diet works by removing carbohydrates that require fermentation by gut bacteria, thus “starving” the overgrowth in the small intestine.
Elemental Diet
You may want to consider the elemental diet for SIBO, especially if you and your healthcare provider choose not to use antibiotics or other complementary therapies, like a course of herbal therapy recommended by your provider. This purely liquid diet comes in powder or liquid form. You’ll stay on the diet for about two to three weeks if you’re being treated for SIBO. Dr. Young says it’s an effective treatment option for SIBO. The formula is easy to digest and contains essential nutrients your body needs in a “predigested” form containing amino acids, fatty acids, vitamins and minerals.
“With the elemental diet, the dietary building blocks and nutrients are more easily digestible and absorbed sooner in the digestive tract, so it’s much less likely to make it to the bacterial source in your small intestine,” she explains. Research shows the elemental diet works. But it only works if you stay with it. That can be a challenge for reasons ranging from the way the formula tastes to being hungry, bored or frustrated because you can’t participate in family or social events that center around food. Working with a registered dietitian or health coach while following the elemental diet can be helpful.
Foods to Include and Avoid
The goal is to make sure you’re eating the right combination of foods that supply the nutrients your body can absorb. Doing so can help starve excess bacteria and create a balanced gut. “Bacteria primarily consume carbohydrates, which results in the production of gases,” explains Dr. Young. “Recommended diet plans aim to decrease certain groups of carbs to both reduce the bacteria and the gas they produce.”
Read also: Elemental Diet Research
Foods to Limit or Avoid
If you have SIBO, you may want to consider reducing or avoiding the following high-FODMAP foods:
- Fruits like apples, pears and cherries
- Vegetables like onions, cauliflower and mushrooms
- Dairy options like milk, ice cream and soft cheeses
- Beans and lentils
- Grains like wheat and rye
- Certain nuts like pistachios and cashews
- Sweeteners like honey and sugar alcohols like xylitol and sorbitol
Other Dietary Considerations
- Fiber: Cutting out fiber completely can backfire in methane SIBO, as it often makes constipation worse. The key is to be selective. Focus on cooked, soft, soluble fibers like peeled zucchini, carrots, or oats.
- Resistant Starches: Resistant starches aren’t fully digested in the small intestine; they reach the colon and ferment there, where they feed hydrogen-producing bacteria. That hydrogen can then be used by methane-producing microbes, which often live in the same neighborhood.
- Fat: While fat itself doesn’t ferment, high-fat meals can slow down stomach emptying. In people prone to constipation or methane SIBO, that extra sluggishness in the upper gut can add to the sense of heaviness and discomfort. This is especially notable with some of the strictest SIBO diet plans that only allow protein foods and low-FODMAP vegetables - it’s easy to end up overdoing fat and protein when carbs are so limited.
- Balanced Meals: Both ends of the spectrum can cause problems: large, starchy meals with little protein can spike fermentation, while very low-carb, high-fat meals can slow digestion. Aim for balanced plates with protein, small portions of tolerated carbs, gentle fiber, and some fat.
- Food Preparation: During symptom management, softer is better. Go for well-cooked veggies, peeled fruits, lean proteins, and simple, familiar ingredients. Think soups, stews, and mashable meals, not raw salads or crunchy snack bars.
Lifestyle and Meal Timing
Small things make a big difference here. Warm fluids in the morning can help kickstart motility. Spacing meals by 3-4 hours (instead of grazing) allows the gut’s natural “cleansing wave” to do its job between meals.
Common Mistakes to Avoid:
Even with the right information, it’s easy to slip into patterns that actually make methane SIBO worse.
- Going too low-fiber and worsening constipation
- Grazing all day - Constant snacking interferes with the migrating motor complex (MMC), a natural cleansing wave in the gut that only activates during fasting.
- Forgetting underlying factors - Slow motility is one of the biggest drivers of methane SIBO, but it’s not the only one. Scar tissue or adhesions from past surgeries, gut-brain signaling issues, chronic stress, low stomach acid from age or long-term PPI use, and even certain medications can all increase the risk of small intestinal bacterial overgrowth.
Sample Meal Plan & Recipe Ideas
Check out this SIBO specific meal plan roundup (categorized by meal type) that will make your life a lot easier while following the SIBO diet!
Breakfast Recipes
- Coconut Raspberry Breakfast Bowl | The Healthy Gut
- Black Forest Smoothie | The Healthy Gut
- Shakshuka | Fun Without FODMAPs
- Mediterranean Grilled Cheese | Fun Without FODMAPs
- Chocolate Strawberry Overnight Oats | Fun Without FODMAPs
- Steel Cut Oats with Maple and Cinnamon | Fun Without FODMAPs
- Frittata | Fun Without FODMAPs
Lunch Recipes
- Pumpkin, Pomegranate and Quinoa Salad | The Healthy Gut
- Tomato and Meatball Soup | The Healthy Gut
- Smoked Salmon Salad | The Healthy Gut
- Crispy Chicken Strips | The Healthy Gut
- Roasted Red Pepper Pasta | Fun Without FODMAPs
- Cilantro Lime Chicken | Fun Without FODMAPs
- Creamy Red Lentil Dhal | The Healthy Gut
Dinner Recipes
- Beef Tacos | Fun Without FODMAPs
- Slow Cooker Pot Roast | Fun Without FODMAPs
- Lemon and Thyme Roast Chicken | The Healthy Gut
- Thai Fish Cakes with Zesty Salad | The Healthy Gut
- Tuna Poke Bowl | The Healthy Gut
- Moroccan Chicken | Fun Without FODMAPs
- Turkey Chili with Sweet Potatoes and Lentils | Fun Without FODMAPs
Snacks & Desserts
- Carrot Cake Bliss Balls | The Healthy Gut
- Kale Chips | The Healthy Gut
- Spiced Trail Mix | The Healthy Gut
- Banana Bread | Fun Without FODMAPs
- Blueberry Yogurt Pots | The Healthy Gut
- Loaded Potato Skins | The Healthy Gut
- Smoked Salmon Blinis | The Healthy Gut
- Chocolate Chip Granola Bars | The Healthy Gut
Have fun experimenting with these recipes and finding your favorites! You won’t feel restricted while following the SIBO diet with these delicious and versatile recipes.
Addressing Root Causes and Seeking Support
If you’ve been dealing with the slow, bloated, constipated misery of methane SIBO, changing your diet can offer real relief. But food is just the starting point. For true treatment, you need to rebalance the gut environment, clear methane overgrowth (when confirmed), and address the root causes that allowed it to develop in the first place. Addressing SIBO fully is something we help clients with every day, guiding them beyond short-term relief toward lasting progress.
One of the more intimidating aspects of dealing with SIBO is the thought that some foods will always be on the no-go list. But Dr. Young notes that food plans to manage SIBO aren’t black-and-white - and what you eat and what you need to limit or avoid can be personalized for you. “After treatment, if you’re feeling better, you can start to reincorporate the FODMAP foods into your diet. They’re often better tolerated,” she adds. “That being said, you may find certain foods will always trigger your symptoms. Those are the ones you may need to continue to avoid or reduce how much of the specific foods you eat.
Additional Diets
This bundle includes four meal plans to reduce symptoms of IBS/SIBO. All sales are final. No refunds.
- Low FODMAP: gluten free
- Plant Based Low FODMAP: dairy free, egg free, gluten free, vegan, vegetarian
- Specific Carbohydrate Diet: gluten free, grain fee, soy free, sugar free
- Plant Based Specific Carbohydrate Diet: dairy free, egg free, gluten free, grain fee, soy free, sugar free, vegan, vegetarian
Common SIBO Questions
- Is the carnivore diet for methane SIBO a good idea? I do not recommend a carnivore diet for methane SIBO. It is extremely restrictive and tends to be very high in protein and fat, which can slow motility.
- What kills methane SIBO naturally? When it comes to what kills methane SIBO naturally, diet alone doesn’t do it-it only helps with symptoms.
- Can coconut milk cause gas with SIBO? Yes, it can. Coconut milk is high in fat, which can slow digestion in methane SIBO, and canned coconut milk is also high FODMAP at larger portions.
- Is oatmeal safe with SIBO? For many people, oatmeal is one of the more tolerable grains with SIBO-particularly rolled or quick oats.
- Is garlic safe with SIBO? Garlic is one of the most common SIBO triggers because it’s high in fructans.
- Do green grapes cause gas? Most of the time, green grapes don’t cause major issues since they’re lower-FODMAP, but everyone’s tolerance is different.
- Is monk fruit safe with IBS or SIBO? Yes.
- What high-fructan foods should I avoid with SIBO? The biggest culprits are onions and garlic (fructans).
- What kind of bread can you eat with SIBO? Bread isn’t totally off-limits.
- Does sugar make SIBO worse? For most people, yes.
- What if I have SIBO and lactose intolerance? Many people deal with both SIBO and lactose intolerance.