Diets For SIBO Management

Benefits of the Elemental Diet and Low-FODMAP Diet

Table of Contents
View All
Table of Contents

Two common small intestinal bacterial overgrowth (SIBO) diet treatments include the elemental diet, a type of liquid diet, and the low-FODMAP diet, which focuses on limiting certain types of carbohydrates that are not easy to digest.

The goal of treating SIBO is to restore an average balance of gut bacteria. SIBO can be the result of several problems, from damage to the gut to certain medications. A SIBO diet can help:

  • Stop the multiplication of “bad” gut bacteria
  • Reduce inflammation
  • Correct nutritional deficiencies

No diet is proven to treat SIBO in every patient, but your provider might recommend a diet plan that can help keep the condition from coming back. Your SIBO treatment plan may also include antibiotics and specific treatments for any underlying health condition you have (e.g., Crohn's disease or irritable bowel syndrome).

This article discusses the use of the elemental diet and low-FODMAP diet for SIBO. It covers what to eat and avoid on a SIBO diet.

man drinking thick shake
Daniel Ingold / Cultura / Getty Images

 If you have SIBO, talk to your healthcare provider and/or a registered dietitian before changing your diet to make sure that you are meeting your daily nutritional needs.

How the Elemental Diet Works for SIBO

The elemental diet is a liquid diet or a powder mixed with water. It is often used for people who have trouble digesting food because they have compromised digestive systems.

The diet gets its name because the nutrients are introduced into the body as close to their primary (elemental) form as possible. 

The elemental diet has been studied as a possible add-on (adjunct) treatment to antibiotics for the following reasons:

  • The nutrients in the diet are believed to be wholly absorbed in the first part of the small intestine, which reduces the number of food components that are available to bacteria.
  • The diet reduces the number of overall gut bacteria, which could mean a reduction in bacteria in the small intestine as well.
  • The diet may increase the amount of bile that gets released from the gallbladder, which could strengthen the small intestine's cleansing wave and reduce bacteria levels.
  • The diet may affect the immune cells in the lining of the intestines, which could help clear up bacteria. 

What to Eat

The elemental diet is given either as a beverage that you drink or through a feeding tube. The amount of liquid you take in slowly increases over the first few days to reduce side effects like diarrhea or abdominal pain.

Each formulation contains nutrients that are in an easy-to-digest form. Typical formulations for the elemental diet include:

Different commercial variations of the elemental diet can be purchased online. The powdered mixes contain only essential nutritional ingredients, providing 150 to 300 calories or more. Your healthcare provider can tell you how much you need to get adequate nutrition.

No artificial flavors or colors are added to elemental diet mixes (which are only combined with water). The beverage has a bland taste that many people find unpalatable. Some experts suggest adding ice to give the drink texture, which can make it easier to drink.

Duration

The length of time you stay on an elemental diet depends on your symptoms and how well you can stick with the program.

One of the biggest challenges of the elemental diet is giving up solid food:

  • According to one published report, only about 25% of patients are willing to restrict their nutritional intake to liquid feeding long enough to see results from an elemental diet.
  • Several studies have shown that compliant patients were able to see results in two to three weeks.

People who cannot take on a complete elemental diet might be able to use a partial essential diet that combines liquid feeding with foods that they are able to tolerate, depending on what their healthcare providers recommend and approve. For some people, this approach might be used for long-term maintenance.

Important Warnings

  • The elemental diet must be used only under medical supervision, as it carries risks.
  • Do not try a homemade elemental diet formulation. Doing so puts you at risk for significant nutritional deficiencies that could negatively affect your health. 
  • The elemental diet is not to be used at the same time as any antibiotic treatment for SIBO.

How the Low-FODMAP Diet Works

One of the first-line treatment options for SIBO is a low-FODMAP diet. FODMAPs are a group of carbohydrates that include:

  • Fermentables
  • Oligosaccharides (comprised of fructans and galactans)
  • Disaccharides (milk sugar lactose)
  • Monosaccharides (fructose)

With SIBO, two FODMAP types—lactose and fructose— might be poorly absorbed because there is inflammation along the small intestine lining. In addition, other non-absorbed FODMAPs may get fermented by the bacteria in the small intestine, leading to symptoms like gas and bloating. 

Following a diet low in FODMAPs can help some people manage their symptoms, but it does not work for everyone. Some research has suggested that the low-FODMAP approach could be beneficial, but more research is needed to know if the treatment is effective enough to be recommended as a standard therapy for SIBO.

What to Eat

During the elimination phase, avoid foods that are high in FODMAPs. High FODMAP foods contain one of the five types of FODMAPs:

  • Fructans. Non-digestible fructans are found primarily in wheat, many vegetables, and some food additives, including inulin.
  • Fructose. Fructose is the sugar in many fruits, honey, and high-fructose corn syrup.
  • Galactans. Also called galactooligosaccharides (GOS), galactans can be found in legumes, including beans, chickpeas, and lentils.
  • Lactose. Lactose is the sugar in milk and other dairy products.
  • Polyols. Sugar alcohols with names that typically end in "-ol” are found naturally in some fruits (like blackberries) and vegetables (such as cauliflower and mushrooms) and are often used as artificial sweeteners.

Almost every food group has options that are high in FODMAPs as well as some that are low FODMAP. 

Low-FODMAP Foods
  • Vegetables: eggplant, green beans, cucumber, lettuce tomato, zucchini

  • Fruits: cantaloupe, grapes, kiwi, strawberries

  • Dairy: feta, camembert, hard cheeses, almond milk, soy milk

  • Protein: eggs, firm tofu, tempeh, seafood

  • Grains: corn flakes, oats, rice cakes, corn pasta, barley-free breads

  • Sweets: dark chocolate, maple syrup, table sugar

  • Nuts and seeds: peanuts, macadamia nuts, sunflower seeds

High-FODMAP Foods
  • Vegetables: asparagus, cauliflower, peas, mushrooms, onions

  • Fruits: apples, cherries, dried fruit, peaches, watermelon

  • Dairy: cow's milk, evaporated milk, ice cream, yogurt

  • Protein: most legumes, marinated meats, some processed meats

  • Grains: wheat, rye, and barley-based breads and snacks

  • Sweets: honey, high-fructose corn syrup, sugar-free treats

  • Nuts and seeds: cashews, pistachios

Duration

The elimination phase of the FODMAP diet can last from two to eight weeks. During this time, you may notice a decrease in your symptoms. 

The next phase, the reintroduction process, is very important. The time needed for this phase varies widely, depending on your symptoms.

Here are a few things to keep in mind:

  • Not every FODMAP type is a problem for every person.
  • You may want to pick one FODMAP sub-group at a time to test and see how it affects you. 
  • Plan to test each FODMAP group for a week before moving on to the next group.

Most experts recommend keeping a food diary to help you get a better sense of the relationship between the foods that you eat and your symptoms. 

The FODMAP diet is not intended for long-term use. Many high-FODMAP foods are an important part of a nutritious, balanced diet. Many also contain prebiotics, which can help keep a healthy balance of bacteria in your gut. 

Recommended Timing

The timing of your meals and snacks is not a factor when following either the elimination or reintroduction phase of the FODMAP diet. You can consume food according to a schedule that works best for you.

However, since re-introducing FODMAP foods may cause symptoms, you may want to pick a time to re-introduce them when you can be at home and take it easy. 

SIBO Diet Considerations

Many people with SIBO have other conditions that may need to be managed with specific treatments, including certain diets:

People with these chronic health conditions may have SIBO and malnutrition. For example, if you have SIBO, fat-soluble vitamins (A, D, E, and K) may not be adequately absorbed in your intestines. You may also be deficient in iron or vitamin B12. If you can’t replenish your stores with food, you may need to take supplements.

You should work with your healthcare provider and a nutrition expert to manage SIBO and any underlying condition that’s contributing to it. Your treatment needs to be tailored to your symptoms and needs. 

What Does Research Say About SIBO Diets?

The research on SIBO diets has been mixed. Some studies have suggested it can be helpful to follow a certain diet if you have SIBO. However, the research has not always been high quality and experts generally say that there is not enough scientific evidence to support a particular diet to treat SIBO.

Here are a few things to consider about the research on SIBO diets:

  • An older study from 2004 found that a 14-day elemental diet was effective at treating SIBO. However, the study used a small number of patients who also had IBS. 
  • A more recent review from 2020 that included the elemental diet as a possible SIBO treatment concluded there has not been enough evidence to support its use. The researchers also noted that an elemental diet can be hard for people to follow and requires help from a provider, which might limit how many people could realistically try it.
  • Studies that have looked at using low FODMAP diets for SIBO point out that this diet plan is commonly advised for people with IBS. Researchers have concluded that it is not clear from the studies that have been done whether following a low FODMAP diet helps with SIBO.
  • Among the studies that noted an improvement, it’s not clear whether people felt better following a low FODMAP diet because the eating plan changed their gut microbiome or because it prevented them from having symptoms related to the gas that is produced by FODMAPs in the GI tract.

Experts do tend to agree that a key part of treating SIBO is to figure out the underlying cause and make sure that it is managed effectively. In some cases, such as for people with chronic diseases that affect their GI system, dietary changes might be part of their treatment.

Summary

While there is no one diet that will cure SIBO and work for everyone, making changes to your diet is likely to be part of your SIBO treatment plan. The elemental and low-FODMAP diets are comfy approaches to SIBO. The goal of these diets is to restore a healthy balance of gut bacteria. 

If you have SIBO, it’s important to work with your provider on a treatment plan that addresses all your symptoms and needs. You may need antibiotics, nutritional supplements, or specific therapies that help you manage an underlying condition that could be contributing to SIBO.

19 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. University of Virginia Health System. Diet for those with symptomatic small bowel bacterial overgrowth.

  2. Jabed Foyez Ahmed, Pritpal Padam, Ruban A. Aetiology, diagnosis and management of small intestinal bacterial overgrowth. 2022;14(2):149-154. doi:10.1136/flgastro-2022-102163

  3. Adike A, DiBaise JK. Small intestinal bacterial overgrowth: nutritional implications, diagnosis, and managementGastroenterol Clin North Am. 2018;47(1):193-208. doi:10.1016/j.gtc.2017.09.008

  4. Rao SSC, Bhagatwala J. Small Intestinal Bacterial Overgrowth: Clinical Features and Therapeutic ManagementClin Transl Gastroenterol. 2019;10(10):e00078. doi:10.14309/ctg.0000000000000078

  5. Pimentel M, Constantino T, Kong Y, Bajwa M, Rezaei A, Park S. A 14-day elemental diet is highly effective in normalizing the lactulose breath testDig Dis Sci. 2004;49(1):73-77. doi:10.1023/b:ddas.0000011605.43979.e1

  6. Functional Nutrition Library. Elemental diet sample.

  7. Gastroenterology Consultants of San Antonio. Low FODMAP diet.

  8. Ghoshal UC, Shukla R, Ghoshal U. Small intestinal bacterial overgrowth and irritable bowel syndrome: A bridge between functional organic dichotomyGut Liver. 2017;11(2):196-208. doi:10.5009/gnl16126

  9. IBS Diets. FODMAP food list.

  10. Whelan K, Martin L, Staudacher HM, Lomer M. The low FODMAP diet in the management of irritable bowel syndrome: an evidence-based review of FODMAP restriction, reintroduction and personalisation in clinical practice. 2018;31(2):239-255. doi:10.1111/jhn.12530

  11. Penn Medicine. SIBO.

  12. Chang MS, Green PHR. A review of rifaximin and bacterial overgrowth in poorly responsive celiac disease. Therap Adv Gastroenterol. 2012;5(1):31-36. doi:10.1177/1756283X11422

  13. Zhang M, Zhu HM, He F, Li BY, Li XC. Association between acute pancreatitis and small intestinal bacterial overgrowth assessed by hydrogen breath test. WJG. 2017;23(48):8591-8596. doi:10.3748/wjg.v23.i48.8591

  14. International Foundation for Gastrointestinal Disorders. Malabsorption.

  15. Achufusi TGO, Sharma A, Zamora EA, Manocha D. Small intestinal bacterial overgrowth: Comprehensive review of diagnosis, prevention, and treatment methodsCureus. 2020;12(6):e8860. Published 2020 Jun 27. doi:10.7759/cureus.8860

  16. Souza C, Rocha R, Cotrim HP. Diet and intestinal bacterial overgrowth: Is there evidence?World J Clin Cases. 2022;10(15):4713-4716. doi:10.12998/wjcc.v10.i15.4713

  17. Shah A, Talley NJ, Jones M, et al. Small intestinal bacterial overgrowth in irritable bowel syndrome: A systematic review and meta-analysis of case-control studiesAm J Gastroenterol. 2020;115(2):190-201. doi:10.14309/ajg.0000000000000504

  18. Bohm M, Siwiec RM, Wo JM. Diagnosis and management of small intestinal bacterial overgrowthNutr Clin Pract. 2013;28(3):289-299. doi:10.1177/0884533613485882

  19. Quigley EMM, Murray JA, Pimentel M. AGA Clinical Practice Update on small intestinal bacterial overgrowth: Expert reviewGastroenterology. 2020;159(4):1526-1532. doi:10.1053/j.gastro.2020.06.090

Additional Reading
Barbara Bolen, PhD

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.