Small Intestinal Bacterial Overgrowth (SIBO) Diet: What to Eat and Avoid

Certain foods and diets may help improve symptoms of SIBO, while others can make them worse, research suggests.
Small Intestinal Bacterial Overgrowth (SIBO) Diet: What to Eat and Avoid
Everyday Health
Small intestinal bacterial overgrowth (SIBO) occurs when too much of the wrong bacteria overwhelms the small intestine, causing symptoms like abdominal pain, nausea, bloating, gas, indigestion, or diarrhea.

 Antibiotics are the standard treatment for SIBO, but diet may play a role, too, says Julia Zumpano, RD, a registered dietitian at Cleveland Clinic in Ohio.

“When you have bacteria overgrowth, there are certain foods that the bacteria like to eat and grow off. We want to avoid those foods,” says Zumpano, who counsels people with digestive issues. “Then there are certain foods that can suppress their growth. That’s the concept behind the different kinds of diet plans you could be on.”

There’s no official “SIBO diet,” and researchers are still learning exactly what role diet plays in SIBO.

Some evidence suggests diets like the low-FODMAP diet, the specific carbohydrate diet, or the elemental diet may be helpful for managing SIBO, says Supriya Rao, MD, a gastroenterologist and medical director of the Obesity Medicine Program at Lowell General Hospital in Massachusetts, who specializes in digestive disorders like SIBO. The best approach often varies from person to person, she adds.

Before trying a new diet, talk to a gastroenterologist or registered dietitian to see if the diet is right for you and for guidance on how to do it safely. These diets are restrictive and are intended to be temporary.

Low-FODMAP Diet for SIBO

The low-FODMAP diet is a diet developed by researchers at Monash University in Melbourne, Australia, to treat irritable bowel syndrome (IBS), a digestive condition closely related to SIBO. It’s also a common approach some doctors use to manage SIBO.

Research on its effectiveness for SIBO is mixed. Some evidence suggests the low-FODMAP diet is helpful for SIBO,

while other research suggests there’s not enough evidence for this. More research is needed.

FODMAPs — fermentable oligosaccharides, disaccharides, monosaccharides and polypols — are a group of carbohydrates that are more difficult for people to digest, Zumpano says. Researchers believe the low-FODMAP diet may help with SIBO because “[FODMAPs] can be poorly absorbed and stimulate and give the bacteria food to grow. This is why they can worsen the digestive symptoms in some people,” Zumpano says.

Certain fruits, vegetables, grains, and proteins are higher in FODMAPs than others. On this diet, you’ll temporarily build your meals around low-FODMAP foods, including: 

  • Eggplant
  • Bok choy
  • Green peppers
  • Carrots
  • Cucumbers
  • Lettuce
  • Potatoes
  • Cantaloupe
  • Kiwi
  • Oranges
  • Pineapple
  • Blueberries
  • Almond milk
  • Brie
  • Feta cheese
  • Hard cheeses
  • Eggs
  • Firm tofu
  • Plain cooked meats, poultry and seafood
  • Rice
High-FODMAP foods should be temporarily avoided. They include:

  • Lactose-based milk, yogurt, and ice cream
  • Wheat-based products, such as cereal, bread, and crackers
  • Beans and lentils
  • Apples
  • Cherries
  • Pears
  • Peaches
  • Artichokes
  • Asparagus
  • Onions
  • Garlic

“You have to be very diligent about having a list available if you haven’t memorized it. It’s important to have a list available when you’re grocery shopping, cooking a meal, eating out or at a social event. That’s the tricky part,” Zumpano says.

The diet is completed in carefully controlled phases you’ll work through with a registered dietitian: an elimination phase, reintroduction phase, and maintenance phase.

 After the six-week elimination of high FODMAP foods, you’ll reintroduce one FODMAP food at a time about every three days, while increasing serving sizes depending on your tolerance.

Importantly, you shouldn’t be on this diet for more than six weeks, Dr. Rao says. “I would never recommend these diets long-term, because you’re cutting out a lot of foods and restricting yourself quite a bit. That can help starve off some of that bad bacteria, but if you don’t start adding in fermented foods after that initial improvement, you’re going to starve off your regular gut microbiome,” Rao says.

Specific Carbohydrate Diet for SIBO

The specific carbohydrate diet (SCD) was developed in the 1920s by the pediatrician Sidney Haas, MD, to treat celiac disease.

 It’s also thought to be helpful for SIBO, though more research is still needed to confirm this.

Similar to the low-FODMAP diet, the SCD involves temporarily avoiding certain grains and grain products with carbohydrates that are difficult to digest, such as bread, pasta, and cereal. The diet is also very low in sugar and lactose, a sugar that occurs naturally in milk and dairy products.

One reason researchers believe the SCD could be helpful for SIBO is that people with digestive disorders have trouble breaking down certain carbohydrates, leaving undigested food particles in the intestines where bacteria can feed on them and grow. But while on the SCD, people steer clear of these carbohydrates, giving their digestive system time for rest and ensuring food doesn’t linger in the digestive tract for bacteria to feed on.

The diet is also low in processed foods, additives and preservatives, which have been linked to gut inflammation. That may also explain why SIBO symptoms ease while on the SCD.

“We're eliminating groups of foods and then slowly adding them back in. So we eliminate to see what the trigger could be and to give your digestive system a break,” Zumpano says.

While on the SCD, you can eat:

  • Additive-free meats
  • Poultry, fish, and seafood
  • Cheeses like cheddar, Swiss, and Colby
  • Fresh, frozen, raw, or cooked vegetables and fruits (without added sugar)
  • Eggs
  • Additive-free and sugar-free coffee, tea, and fruit juice
  • Certain legumes, such as lentils or split peas
  • Most nuts and nut flours
  • Honey as a sweetener
Foods you must temporarily avoid on the SCD include:

  • Grains, including barley, corn, oats, quinoa, rice, and wheat
  • Grain products, like cereal, pasta, and bread
  • Sugar, molasses, and maple syrup
  • Milk and lactose-containing milk products
  • Candy, chocolates and other sweets made with sugar and high fructose corn syrup
  • Canned vegetables with additives
  • Potatoes, sweet potatoes, and turnips
  • Canned and most processed meats

Again, this diet shouldn’t last longer than six weeks. After that, you’ll need to gradually reincorporate grains into your diet. “It eliminates processed foods, which is good, but it’s cutting out a lot of fiber, which I don’t love,” Rao says.

Elemental Diet for SIBO

If you’ve exhausted the standard treatment options, including antibiotics and the short-term elimination diets noted above, your gastroenterologist or registered dietitian may opt to put you on an elemental diet.

The elemental diet is a temporary, restrictive liquid meal replacement diet. For two weeks, you’ll consume all your meals in the form of a liquid or powder formula that contains all your nutritional and caloric needs broken down into an elemental (“predigested”) form. This approach allows your digestive system to rest and recover.

Dosages are prescribed specifically to your size, height, weight, and activity levels, Zumpano says. “It’ll have the appropriate amounts of fats, carbs, and protein broken down into amino acids, and then it’s combined with your vitamins, minerals and electrolytes. And that’s all you consume,” she says. With this diet, excess bacteria has nothing to feed on and will gradually die off.

Researchers found that, among people with IBS and SIBO who were on the elemental diet, 80 percent recovered within 14 days, and another 5 percent recovered after 21 days.

Despite its effectiveness, consider the elemental diet a last resort for treating SIBO because of its restrictiveness, Rao and Zumpano say.

Foods You May Need to Avoid if You Have SIBO

As mentioned, certain foods may worsen SIBO symptoms by feeding bacterial overgrowth and irritating a sensitive digestive system. Work with a gastroenterologist or registered dietitian to identify which foods worsen your symptoms or trigger SIBO flare-ups, and which seem to soothe your digestive tract, Zumpano says.

“You can journal along the way to make sure you’re noting symptoms associated with the food you’re eating. That’s essential when it comes to the low-FODMAP or any type of elimination diet,” Zumpano says. “I also recommend having meal plans or preparing meals ahead of time with safe foods.”

Certain foods are more likely than others to aggravate SIBO, says Rao. They include:

  • High FODMAP foods, including onions, garlic, tomatoes, and wheat
  • Dairy products that contain lactose: “As patients get older, lactose is one thing that they all of a sudden realize they can’t really handle and digest anymore,” Rao says.
  • Processed foods and artificial sweeteners
  • Large quantities of high-fiber raw vegetables and legumes
  • Carbonated drinks and alcohol

There may be factors you need to consider beyond diet, Rao notes. Along with your diet, consider your sleep health, exercise levels, and stress levels, which can also play a role in digestive issues. “People think that taking a magic pill or going on a restrictive diet is going to solve everything, but it’s multifaceted. If you’re not sleeping well, eating well, or taking care of yourself, this will affect your digestion,” she says.

The Takeaway

  • There’s no official “SIBO diet,” but gastroenterologists and registered dietitians may recommend certain diets that temporarily eliminate certain foods to limit the growth of harmful bacteria.
  • There are several commonly recommended options, such as the low-FODMAP diet, but more research is needed to confirm the effectiveness of dietary approaches for SIBO.
  • If you’re considering a diet for SIBO, talk to a gastroenterologist or registered dietitian with expertise in SIBO before trying it. They’ll help you safely eliminate certain foods from your diet temporarily and then gradually reintroduce foods into your diet.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. SIBO. Cleveland Clinic. August 9, 2024.
  2. Souza C et al. Diet and intestinal bacterial overgrowth: Is there evidence? World Journal of Clinical Cases. May 26, 2022.
  3. Roszkowska P et al. Small Intestinal Bacterial Overgrowth (SIBO) and Twelve Groups of Related Diseases — Current State of Knowledge. Biomedicines. May 7, 2024.
  4. Wielgosz-Grochowska JP et al. Efficacy of an Irritable Bowel Syndrome Diet in the Treatment of Small Intestinal Bacterial Overgrowth: A Narrative Review. Nutrients. August 17, 2022.
  5. High and low FODMAP foods. Monash University. March 2025.
  6. FODMAP Diet: What you need to know. Johns Hopkins Medicine. March 2025.
  7. Low FODMAP diet. Cleveland Clinic. February 24, 2022.
  8. The Specific Carbohydrate Diet. Stanford Medicine.
  9. Specific Carbohydrate Diet. Cleveland Clinic. July 19, 2022.
  10. Elemental Diet. Cleveland Clinic. November 18, 2021.
  11. Nasser J et al. Elemental Diet as a Therapeutic Modality: A Comprehensive Review. Digestive Diseases and Sciences. July 13, 2024.
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Ira Daniel Breite, MD

Medical Reviewer

Ira Daniel Breite, MD, is a board-certified internist and gastroenterologist. He is an associate professor at the Icahn School of Medicine at Mount Sinai, where he also sees patients and helps run an ambulatory surgery center.

Dr. Breite divides his time between technical procedures, reading about new topics, and helping patients with some of their most intimate problems. He finds the deepest fulfillment in the long-term relationships he develops and is thrilled when a patient with irritable bowel syndrome or inflammatory bowel disease improves on the regimen he worked with them to create.

Breite went to Albert Einstein College of Medicine for medical school, followed by a residency at NYU and Bellevue Hospital and a gastroenterology fellowship at Memorial Sloan Kettering Cancer Center. Working in city hospitals helped him become resourceful and taught him how to interact with people from different backgrounds.

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Carmen Chai

Author

Carmen Chai is a Canadian journalist and award-winning health reporter. Her interests include emerging medical research, exercise, nutrition, mental health, and maternal and pediatric health. She has covered global healthcare issues, including outbreaks of the Ebola and Zika viruses, anti-vaccination movements, and chronic diseases like obesity and Alzheimer’s.

Chai was a national health reporter at Global News in Toronto for 5 years, where she won multiple awards, including the Canadian Medical Association award for health reporting. Her work has also appeared in the Toronto Star, Vancouver Province, and the National Post. She received a bachelor’s degree in journalism from Ryerson University in Toronto.