There are literally HUNDREDS of different diets recommended for Small Intestine Bacterial Overgrowth (SIBO)
– which means it can be really overwhelming and confusing to get started.
Should you try low-FODMAP or Elemental? Gluten-free or low-fermentation? Vegan or all meat? Should we be eating to feed the gut bugs or starve them? Are apples allowed or are they forbidden?!? HELP!
People ask me about this all the time, so today I want to help cut through all the clutter and talk about the “Big 6” diets for SIBO – these are the diets that I hear recommended from the top practitioners most often.
(There are definitely more than 6 effective SIBO diets – and you may have found one that works for you that isn’t on this list! That doesn’t mean you’re doing anything wrong. We all have to find our own path in SIBO treatment.)
Here are the diets I’m going to cover:
- The Low-FODMAP Diet
- Cedars-Sinai Low Fermentation
- The SIBO Specific Food Guide
- The Bi-Phasic Diet
- The Fast Tract Diet™
- The Elemental Diet
Before I dig into the diets themselves, I’ll briefly talk about what diet can and can’t do, and why diet is used in SIBO treatment.
Why Use Diet for SIBO?
There are several reasons to use diet in SIBO treatment:
- Diet is used in conjunction with antibiotic or herbal antibiotic treatment for SIBO. These treatments take time to work, and changing your diet can provide symptom relief during treatment. Some diets can also increase the effectiveness of antibiotic or herbal treatments. Some doctors prescribe diets before drug treatments to help manage die-off, too. In these cases, diet is usually a temporary change, and then patients return to their normal way of eating (or close to it).
- Diet provides relief for those with chronic SIBO. Some people have an underlying cause that causes SIBO to recur or never be completely resolved. They’ve tried drug or supplement treatment without results (or with frequent relapses). For those people, diet is a powerful tool to treat symptoms so that they don’t have to suffer! These people will follow the diet (typically modified to their exact needs) long-term.
- Diet can be the only treatment some people are willing to do. There are lots of reasons why someone may not want to treat SIBO with drugs or supplements – from financial to personal beliefs. Diet can’t “cure” SIBO, but it can resolve your SIBO symptoms, so some people choose to use diet alone to manage SIBO. Diet usually has to be followed long-term to provide ongoing symptom relief. (The only exception to this might be the Elemental Diet – more on that to come!)
- Diet can help prevent relapses. After treatment, following a modified diet (usually along with a prokinetic) can help prevent SIBO from recurring.
What All SIBO Diets Have In Common
All SIBO diets have one thing in common: they work by addressing carbohydrate malabsorption.
Most (but not all) symptoms in SIBO are caused by carbohydrate malabsorption.Carbohydrate malabsorption is when carbohydrates in particular bypass absorption in the small intestine and get left in the lumen, aka the inside tube of the large or small intestine. Because they haven’t been digested, they ferment (get eaten by bacteria) and create gas. The gas causes symptoms like bloating, flatulence, and diarrhea.
All SIBO diets work by restricting carbohydrates in one way or another – usually by avoiding a specific type of carbohydrates.
Want to learn more about how SIBO causes carbohydrate malabsorption and the underlying causes of SIBO? Go here.
What Makes Each SIBO Diet Unique
We now know all SIBO diets work be restricting carbohydrates – but they all take a slightly different approach to how, which, and why carbs are restricted. And one diet goes a totally different direction.
Let’s get to it!
The Low-FODMAP Diet
The Low-FODMAP diet was created by Dr. Sue Shepherd and Dr. Gibson from Monash University in Australia as a treatment for Irritable Bowel Syndrome. It works by restricting certain types of carbohydrates: fermentable oligo-, di-, mono-saccharides and polyols (FODMAPs).
Common high-FODMAP foods include things like milk, asparagus, broccoli, apples, wheat, and beans. You can find lots of lists of high and low-FODMAP foods online or use apps like the Monash University Low FODMAP Diet app.
Some people need to restrict all kinds of FODMAPs, while others might find they only have problems with one or two kinds, like polyols or oligosaccharides.
SIBO expert Dr. Allison Siebecker suggests The Low-FODMAP diet for those with mild SIBO who can tolerate more foods and for those are struggling to gain weight, as the low-FODMAP diet allows more carbohydrates than most other SIBO diets. She also uses it after treatment alongside prokinetics to help prevent relapse.
Low-FODMAP is one of the best options for vegetarians and vegans with SIBO because it includes some less-fermentable beans and legumes that can be used a protein source.
But what makes The Low-FODMAP diet a good choice for some means it doesn’t work well for others. Because it is less-restrictive than other diets, it doesn’t provide symptom relief for all people. It allows foods like fiber, starch, and resistant starch which can cause symptoms for some people with SIBO.
The Cedars-Sinai Low Fermentation Diet
The Cedars-Sinai Low-Fermentation Diet was created by Dr. Mark Pimentel to treat IBS and to help prevent SIBO relapse after treatment. According to Dr. Siebecker, this diet can cause an average of 60-80% reduction in symptoms.
The Low-Fermentation focuses on reducing complex carbs and carbs that are likely to ferment in the stomach – things like whole grains, brown rice, and artificial sweeteners. Instead, you’ll eat carbs that digest more quickly – like white bread, white rice, and potatoes.
Like the Low-FODMAP diet, the Low-Fermentation diet is good for those with mild SIBO or who have other food restrictions, like vegetarianism. Some people perceive the Low-Fermentation diet as the easiest diet to follow – so if you hate being on a restricted diet, this one might be the one for you!
If your SIBO is severe, the Low-Fermentation diet might not be restrictive enough to help manage your symptoms.
The SIBO Specific Food Guide
The SIBO Specific Food Guide was created by SIBO expert Dr. Allison Siebecker. Combining principles of the Specific Carbohydrate Diet (one of the oldest diets used for gut disorders) with the Low-FODMAP diet.
Created specifically to help treat SIBO and is one of the most successful diets for treating SIBO symptoms and restricts both food AND quantities of allowed foods (for instance, 20 almonds at a time instead of unlimited quantities).
Why does it work so well? Probably because it restricts the most carbohydrates of any of the diets we’ve talked about so far!
If your SIBO symptoms are very severe, the SIBO Specific Food Guide is the option for you. It averages between 75 and 90% reduction in symptoms.
The drawbacks? The guide can be difficult to follow if you’re vegetarian and can cause weight loss because it is so restricted. Some people find it too difficult to stick to.
The Bi-Phasic Diet
The Bi-Phasic Diet was created by Dr. Nirala Jacobi and is based on the SIBO Specific Food Guide. It’s split into two phases: one for before treating SIBO with antimicrobials and one for during and after treatment.
The goal with the first phase is to reduce the amount of overgrowth so that die-off symptoms are less severe. The second phase is done alongside antibiotic or herbal treatments.
Like the SIBO Specific Food Guide, the Bi-Phasic diet is very restricted – so it tends to have very good results – again 75-90% reduction in symptoms.
The Bi-Phasic diet is very structured – so if you’re someone who likes to know exactly what to eat and avoid, this may be a good choice for you. If you prefer a more flexible diet, this protocol might not be a good fit for you.
The Fast-Tract Diet™
The Fast Tract Diet™ was developed by microbiologist Dr. Norm Robillard using a mathematical equation paired with the Glycemic Index to assign foods a “Fermentation Potential” value.
Depending on your symptoms you’ll set a goal number to stay under per day, and then count the “FP” in everything you eat.
The Fast Tract Diet™ reminds me of Weight Watchers – you choose a goal number and count the points in everything you eat. And just like Weight Watchers, there’s an app you can download to help you find and track the FP points of everything you eat.
If your symptoms are still severe, you can reduce the number of FPs you eat per day – and as you improve, you can increase the number of FPs you eat each day.
One of the easiest diets to follow if you eat out or travel a lot. And many people love the simplicity and structure of this diet. Following it is straightforward!
The Elemental Diet
The Elemental Diet is very different from the 5 other diets we’ve discussed so far. Unlike the other SIBO diets, the Elemental Diet is a therapy in itself. It shouldn’t be the first diet you try – in fact, it should only be considered for tough cases who have already failed other SIBO treatments.
A liquid diet that can be both antibacterial and anti-inflammatory while also helping repair the gut. (There is also a Semi-Elemental Diet, but according to Dr. Michael Ruscio the effectiveness of both the full elemental and semi-elemental diets are the same.) It is followed for 2-3 weeks at a time.
This is not the same as fasting (or modified fasting) – on the Elemental Diet, you’ll drink a specially formulated blend of nutrients to get your daily calorie needs met.
The proteins in the Elemental Diet are broken down into the most elemental form – amino acids.
The carbohydrate contained in the element is fully digested, and so it essentially contains no fiber which can be very helpful for sensitive guts.
You can purchase a pre-made Elemental Diet or create your own at home using store-bought ingredients.
For some severe SIBO cases, the Elemental Diet is a lifesaver. It is the only diet that cure SIBO.
But for other people, it’s way too restrictive and can cause weight loss.
Is There A Perfect Diet For SIBO?
NO! There is no one perfect diet for everyone with SIBO. We all have different symptoms AND different personalities. What works for me might make you feel worse. It’s highly individual.
Finding the right diet for you is a learning and trying process.
But because diet is not enough to kick chronic SIBO to the curb, check out our SIBO roadmap here – a nine step proven method for treating SIBO.
I hope this breakdown has helped you better understand the options available!