The New SIBO Diet A commentary for practitioners  By Dr Nirala Jacobi BHSc ND

As most SIBO practitioners know, the SIBO Diet for patients can be very restrictive due to its low fermentable fibre content. Often, patients come into my office for the first time having self-prescribed the low FODMAP diet and still suffer from SIBO symptoms.

For the past few years, I’ve been promoting what I call the "SIBO Bi-Phasic Diet". Now I've updated the diet, and we've added a brand new handout to our website.

The New Bi-Phasic Diet, as the name implies, has two distinct phases, each lasting an average of six weeks. In this SIBO Diet,  Phase One is further divided into restricted and semi-restricted groups to allow for some movement within this phase. Patients typically start with the most restrictive diet and moving through the phases as their symptoms improve.

In the past, I’ve recommended the use of antimicrobials in phase 1 for an average of six weeks, depending on the patient’s hydrogen or methane gas levels.  Though a tough diet to follow, this dietary approach has very successful in the treatment of SIBO for hundreds of SIBO sufferers.


So what is the NEW SIBO Bi-Phasic diet?


My rethinking of this diet has come about through my pondering on Dr Pimentel’s stance on "feed the bacteria whilst you kill them" as well as through a lengthy conversation I’ve had with Dr. Allison Siebecker – both renowned SIBO experts.

"Feed the bacteria whilst you kill them" – is an older concept based on the belief that bacteria go into a state of senescence or hibernation when deprived of a food source. Dr Mark Pimentel, therefore, advises his patients do not follow any particular diet whilst on Rifaximin or other antibiotics to affect maximum kill rate. Whilst this argument makes perfect sense, I have not seen this be an effective strategy when using herbal antimicrobials. The reason may be due to the fact that the average herbal treatment will typically last 4- 6 weeks.  I just have a hard time telling gut-sensitive patients to eat a high fermentable fibre diet. In my experience, this leads to symptom exacerbation in most of them.

Furthermore, I have never needed to do this whilst treating any other gut infection be it candida, H.pylori, or parasites in my almost 20 years in practice—natural medicine practitioners typically use the highly successful dual approach of diet and antimicrobials in all of these cases.


Why would SIBO be different?

In my conversation with Dr Allison Siebecker of the SIBO Centre in Portland USA, we both pondered this conundrum of feeding vs starving whilst treating.

The solution? Tweaking the biphasic treatment to accommodate a little of both. I’ve seen encouraging results so far. Grab Your SIBO Bi-Phasic Diet and let's get started.


The SIBO Bi-Phasic Diet




Reduce: The first phase of the diet focuses on reducing fermentable starches and fibres which is necessary to starve bacteria of their preferred fuel so they’ll begin to die-off.

Repairing the damage to the integrity of the intestinal lining as well as repairing proper digestion is another key element of this phase. Patients may benefit from digestive support, gut healing nutrients and targeted probiotics to repair the intestinal lining and digestive processes during this phase This phase is divided into two groups to be able to adjust the strictness of the diet.

  • Phase 1 restricted diet — everyone starts with this diet. Some have to stay on this diet for the entire six weeks. How quickly the patient can move to the semi-restricted diet depends on how quickly their symptoms improve. If symptoms are greatly improved after the first week, patients move to the semi-restricted diet and go back to the restricted diet if they suffer a relapse of symptoms at any point during treatment.
  • Phase 1 semi-restricted diet – this diet builds on the restricted diet but allows for some starches such as rice and quinoa. The practitioner may recommend starting at this level if the patient is prone to rapid weight loss or need more energy from starches.




Remove: remove remaining overgrown bacteria and fungi from the small intestines: In this phase of the protocol, antimicrobials will be prescribed. Even though still a low fibre diet, the protocol becomes a bit more lenient to allow for some bacterial growth so that antimicrobials may be more successful.

Restore: the restoration of the normal motility of the small intestines is important to prevent relapse of SIBO. In this phase you may want to recommend pro-kinetic medication or supplements. This phase builds on the allowable foods from phase one.

With this new approach of not starting herbal antimicrobials until the patient is on a less restrictive diet serves two purposes:

  1. The restrictive nature of Phase One will reduce some bacterial load already, resulting in less "die-off" when antimicrobials are started
  2. Starting the herbs during Phase Two will ensure a little feeding of bacteria as this diet has slightly increased fermentable fibres from phase 1

Want To Read More? Get the latest SIBO Bi-Phasic Diet  




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